- Security chiefs held talks over the terror threat to Parliament, PM reveals
- Comes after a gunman rampaged through Canada's parliament in Ottawa
- Muslim convert named Michael Zehaf-Bibeau shot and killed a soldier
- He was stopped from killing more by heroic sergeant at arms Kevin Vickers
Security chiefs are holding emergency talks over the terror threat to Parliament and other major landmarks following the lone-wolf gun attack in Canada, David Cameron revealed today.
The heads of MI5 and Scotland Yard met this morning to review 'the security of institutions in central London', the Prime Minister said.
It came after a gunman rampaged through Canada's parliament in Ottawa before being shot dead by the heroic sergeant at arms Kevin Vickers.
David Cameron said Britons needed to remain in a state of 'permanent vigilance'
Muslim convert named Michael Zehaf-Bibeau shot and killed a soldier at the city's war memorial before launching his attack on the parliament.
Mr Cameron today urged the British public to maintain 'permanent vigilance' in the face of the global terror threat.
But he said: 'Meetings are taking place to ensure we have all the angles covered.'
Mr Cameron, speaking to the BBC's Asian Network, said: 'I was in a meeting with the Metropolitan Police commissioner and the head of MI5 when the news about Ottawa broke.
'They immediately reassured me that they had been looking at the security of institutions in central London but they would look again to see if there was more that can be done.
'Those meetings are this morning. But from every- thing I see I know we are taking steps across the board to meet the threats we face as a country.'
He said the outrage in Ottawa 'shows that we have to be permanently vigilant against this sort of terrorist threat'.
The UK's terror threat level was raised from 'substantial' to 'severe' — meaning an attack is highly likely — in late August amid fears of a terrorist strike linked to Islamic State or another extremist group.
Parliament's joint security committee will meet shortly. Its chairman Greg Hands told the Standard: 'I'm sure Canada and what happened there will feature in our discussions.
'It's no secret the Canadian Parliament and UK Parliament are two of the most similar legislatures, both in operation and physical building.'
Guidance to people working at Westminster on what to do if gunmen get into one of the buildings may also be updated and re-sent.
Commons authorities have previously advised that if there is a terror attack on Parliament people should try to get fully away rather than hide in offices.
Commons Leader William Hague told MPs he is to send a message of solidarity from the British Parliament to Canada. Labour leader Ed Miliband also said in a speech at Rochester, Kent: 'We stand in solidarity with the Canadian people.'
In Canada, the country's MPs today hailed sergeant-at-arms Kevin Vickers after his swift actions put a stop to the attacker's hail of gunfire.
Mr Vickers, a 58-year-old former Canadian Mountie, shot the assailant.
Vickers has been the House of Commons' head of security since 2005 and will now go down in history as one of its most memorable after he bravely pursued and took down Zehaf-Bibeau.
Despite working for the police for three decades, relatives said the incident was the first time in his career that Vickers had ever shot anyone.
Riveting video taken inside Ottawa's House of Commons makes startlingly real just how heart-thumpingly dangerous the situation was that Vickers heroically diffused.
A rush of armed police can be seen running toward an unseen suspect as the video from Globe and Mail opens.
At the head of the pack is a man moving swiftly with his gun in hand toward Zehaf-Bibeau, who had moments before murdered a reservist who stood guard at Canada's Tomb of the Unknown soldier.
The death of that man, a 24-year-old father of a young son, Nathan Cirillo, would soon be avenged as Vickers takes aim inside the cavernous parliamentary building and fires off multiple shots.
As those shots echo throughout the hall, the video goes wobbly as the men behind their leader Vickers move for cover.
'MPs and Hill staff owe their safety, even lives, to Sergeant at Arms Kevin Vickers who shot attacker just outside the MPs' caucus rooms,' tweeted New Democrat MP Craig Scott.