Streatham terrorist Sudesh Amman was one of 74 convicted terrorists let out on licence in Britain under an automatic early release scheme brought in 15 years ago.
The 20-year-old who was shot dead by police in South London after stabbing two people on Sunday had been freed from prison less than a fortnight earlier.
Fears have now been raised over how many more jihadis are roaming Britain's streets with police said to be monitoring at least 20 of them on a daily basis.
It comes after Usman Khan, who killed two people in the London Bridge attack on November 29 last year, was let out despite a judge saying he should not be freed.
Here are a series of convicted terrorists and hate preachers who have been freed, many of whom were granted early release in Britain:
Kazi Islam a loyal follower of Anjem Choudary, was allowed out to go and live next to his uncle Kazi Rahman, who is also a convicted terrorist, in Manor Park, East London. Islam was put behind bars for plotting to kill British soldiers, but he was freed last year after serving just half of his eight-year sentence. He tried to groom a vulnerable teenager with learning difficulties and convince him to buy ingredients for a pipe bomb.
Kazi Rahman who is Kazi Islam's uncle, was jailed for a string of terror offences in 2006 but later released. He is a convicted terrorist and associate of the banned terror group Al Muhajiroun that Anjem Choudary used to lead. Rahman had tried to buy missiles to shoot down planes, a rocket-propelled grenade launcher and Uzi submachine guns. But Rahman, a plumber from East London, was released from jail in 2011.
Mohammad Shahjahan was one of the eight terrorist plotters jailed along with London Bridge attacker Usman Khan in 2012. He was part of an Al Qaeda-inspired cell which plotted to blow up the London Stock Exchange and kill Boris Johnson. Shahjahan was one of three initially handed indefinite prison terms, but the trio won an appeal in 2013 which changed them to fixed sentences. Shahjahan was then re-sentenced to 17 years and eight months, and is thought to have been let out in 2018.
Shah Rahman was part of a terror gang who planned a Mumbai-style bomb blitz in London. The four Muslim fanatics intended to unleash a Christmas campaign of atrocities with targets including the Stock Exchange and Big Ben. They could have expected a sentence of 20 years, but at the 11th hour decided to plead guilty after a judge indicated they would receive lesser sentences for admitting the plot. Rahman was was jailed for at least 12 years in 2012 but has already been released on licence.
Anjem Choudary was jailed for five and a half years for inviting support for a terrorist organisation when he swore an oath of allegiance to Islamic State. The hate preacher was released automatically on licence in October last year after serving less than half his sentence. The father of five is now thought to be living back in his family home in East London where he previously masterminded an Islamist extremist network.
Royal Barnes, who had been associated with of one of Lee Rigby's murderers, pleaded guilty to posting sickening videos on YouTube glorifying the horrific killing. Barnes, of Hackney, East London, and his wife Rebekah Dawson, recorded and uploaded three videos shortly after the murder in Woolwich in 2013. He was jailed for five years and four months - and in one clip could be seen laughing as he drove past floral tributes to Rigby.
Ibrahim Abdullah-Hassan, a member of the now banned group Al Muhajiroun, was arrested in May 2013 after being interviewed on BBC Newsnight and claiming MI5 had offered a job to his friend Michael Adebolajo, the killer of Lee Rigby. He was jailed in 2014 for three years for inciting terrorism then later released. He had his sentence reduced by nine months despite also calling for Tony Blair's assassination.
Gabriel Rasmus was jailed for years and three months in 2017 after an undercover police operation revealed his plans to join ISIS by escaping Britain in the back of a lorry. Rasmus boasted if he stayed in Britain 'he would commit a terrorist attack here', and praised the Charlie Hebdo attackers a for doing a 'good job'. South African national Rasmus, a former worker at Swarovski fashion accessories on Regent Street in London, pleaded guilty to seeking to join ISIS on his fifth attempt.
Houria Chahed Chentouf was sentenced to two years in prison after admitting concealing 'a mini encyclopedia of weapons making' in the sleeve of her burka. But the memory stick fell out in front of police when she was stopped at Liverpool's John Lennon airport after she arrived from Holland. It contained more than 7,000 files that might have been useful to terrorists. Upon being sentenced in November 2009, she was already free to go having served 382 days on remand since her arrest.
Habib Ahmed, a Manchester taxi driver, was jailed for ten years - nine for being a member of a terror group and an additional one year for possessing a document for terror-related purposes in 2008. But he was freed on licence after serving less than a third of his sentence. He was caught in possession of two diaries which had details of top Al Qaeda operatives written in invisible ink - described as a terrorist's contact book.
Khuram Iqbal, a student from Cardiff, called himself the 'Father of Terrorism' while posting links to extremist videos on Facebook and Twitter. He fled to Kenya in 2011 but was deported back to Britain after being arrested 12 miles from the Somali border in October 2013. Iqbal admitted disseminating terrorist publications after posting more than 800 links and was jailed for three years and three months in September 2014.
Mohammed Benares, a Royal Mail worker, who had links to Anjem Choudary, was jailed for two years for terrorism offences in 2013. He had terror guides showing how to make a bomb and detonator and how to handle an AK47 assault rifle. Benares, of Birmingham, was said to have been released well before the end of his term.
Omar Latif was part of the cell jailed for the plot to blow up the London Stock Exchange with London Bridge attacker Usman Khan. He was jailed for ten years and four months in 2012 for assisting in preparation for terrorism, plus a further five on extended licence – and is thought to have been freed last year automatically halfway through his sentence.
Shah Jalal Hussain had his 2008 sentence for fundraising for terrorism in Iraq and breaching bail reduced by nine months. In 2014 he was jailed a second time for encouraging terrorism and spreading terrorist propaganda online and then released again the following year. But since his second release, he has been allowed to spread support for hate preachers on Facebook.
Simon Keeler was jailed for two years in 2016 after being caught heading towards the Middle East despite being told he could not leave the UK. The Islamic hate preacher and friend Trevor Brooks were arrested in Hungary on a train bound for Romania. The pair had both been convicted in 2008 on terrorism charges. He was the first white British Muslim to be convicted of terrorism offences.
Trevor Brooks, also known as Abu Izzadeen, acted as Al Muhajiroun's internal enforcer. The London-born convert was jailed for four and a half years for terrorist fundraising and inciting terrorism, and released in May 2009 after serving three and a half years, including time on remand. He and friend Simon Keeler were jailed for two years in 2016 after travelling towards the Middle East, but have since been released.
David Souaan, a radical Muslim student who wanted the black flag of ISIS to fly over Downing Street, was jailed in 2015. He was found guilty of planning to join rebel forces in war-torn Syria. Souaan had visited the country in 2013 and was on his way back to fight the jihadist cause when he was arrested at Heathrow. He was jailed for three-and-a-half years but served 13 months before being released on licence after eight months on remand.
Iftikhar Ali was jailed for more than three years in January 2018 after sending WhatsApp text messages glorifying terrorism. The Sainsbury's shop assistant was arrested over a payment of £140 via Western Union to a man in Turkey, which he claimed in police interviews was for 'charitable purposes'. After his arrest, counter terrorism officers discovered he had typed 'Kuffar', 'Jihad' and 'Sharia4UK' into his phone so much the terms were stored in the device's user dictionary. He was released last year.
Imran Mahmood was jailed for more than nine years in 2013 for his involvement in a plot to attack soldiers in Royal Wootton Bassett and murder the heads of MI5 and MI6. He was caught at Manchester Airport bringing two rucksacks with traces of explosives on them back from Pakistan. Mahmood is thought to have been released in 2019 after serving two thirds of his sentence. He was sentenced alongside Jahangir Alom, a former police community support officer, ex-BBC security guard Richard Dart.
Jahangir Alom, a former Metropolitan Police community support officer, was also convicted over the plot to attack Wootton Bassett. Bangladesh-born Alom was jailed for four years and six months in 2013 after being convicted with Richard Dart and Imran Mahmood. He had said in a YouTube video that he left the police force after 'brothers' showed him the true path.
Jordan Horner was one of three members of a so-called 'Muslim Patrol' who was jailed in December 2013 for repeatedly trying to enforce Sharia law in East London. Horner and another Islamic extremist told one couple they could not hold hands while walking down the street, because it was in a 'Muslim area'. Horner was jailed for 17 months in 2013, then released on licence the next year.
Mizanur Rahman, an associate of Anjem Choudary, was jailed for five-and-a-half years in 2016 alongside Choudary for inviting support for Islamic State. He had been released in 2010 after serving three quarters of a four-year sentence for soliciting murder, before being arrested again in 2014. Rahman was released from prison in October 2018. Last February he was banned from being involved in the running of schools in order to protect children from 'dangerous influences'.
Umran Javed was jailed for six years in 2007 after calling for American and Danish people to be murdered during a protest in London against cartoons depicting the Prophet Muhammad. Javed, of Birmingham, was a former spokesman for Al Muhajiroun. He served half his sentence before being re-arrested in 2012 for possession of terrorist-related material. Javed served six weeks of a year-long term after his remand period was taken into account.
Abdul Muhid, also known as Abu Walaa, was convicted of soliciting murder in 2007 during the Danish cartoon row, alongside Urman Javad and Mizanur Rahman. While in jail he is said to have set up www.muslimprisoners.com, a website where inmates were able to voice their hate-filled opinions. Muhid, who is an ex-member of Al-Muhajiroun, has since been released.
Abdul Rahman Saleem was an Islamic activist sent to prison for four years in April 2007 after being convicted of inciting racial hatred during a protest in London against the publication of cartoons of the Prophet Mohammed. He was also filmed shouting '7/7 on its way'. However he served less than three years in prison and was released in August 2009.
Umar Arshad was an Al Qaeda inspired terrorist was sentenced to six years and nine months in prison for his part in a plot to blow up a Territorial Army base in Luton with a bomb strapped to a toy car. A four-strong terror gang also discussed attacking MI5, the US Air Force, English Defence League and their local shopping centre. He is thought to have served half of his prison sentence.
Syed Farban Hussain was also involved in the plot to blow up the TA base in Luton by sending a bomb in a toy car. Hussain was jailed for five years and three months in April 2013 and is believed to have been released having served half of his sentence. After being arrested in a major operation by the police and security services, the four men admitted a joint charge of preparing for terrorism.
Syed Choudhury was jailed for more than three years for plotting to fight for ISIS and said 'all gay people should be killed'. The Cardiff student, whose family are from Bradford, trawled the internet for terrorist material and told friends he 'would do anything' to get to Syria. Choudhury downloaded a video of a mass execution and had accessed websites called '10 reasons to join ISIS'. He admitted preparing for acts of terrorism but has since been released.
Asfor Ali was jailed for two years and seven months in 2014 after being found guilty of possessing a library of terror manuals. The London Underground security worker warned of a terror attack during the Duke and Duchess of Cambridge's wedding. He kept a stash of al-Qaeda documents, bomb-making plans and extremist lectures on his computer and bragged that the 9/11 attacks were a blessing. However, Ali was released after 11 months in prison.
Rebekah Dawson is a Muslim convert from Hackney, East London, who was jailed for six months in 2014 after refusing to remove her niqab in court. She made three videos glorifying the murder of Fusilier Lee Rigby, and was also sentenced to a further six months for terrorising a security guard at the Finsbury Park Mosque in North London because he allowed non-Muslim women inside without veils.