Canadian Prime Minister Stephen Harper hid in a cupboard for 15 minutes when a masked gunman stormed Parliament in a terrifying attack that left the nation's capital on lockdown.

MPs sharpened flagpoles to use as spears and barricaded the doors while Muslim convert Michael Zehaf-Bibeau exchanged dozens of shots with guards inside Canada's Parliament building.

He fatally shot Corporal Nathan Cirillo, a 24-year-old father, as he stood guard at the War Memorial in Ottowa on Wednesday morning.

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Prime Minister Stephen Harper was hidden in a cupboard for 15 minutes when a masked gunman stormed the Canadian Parliament building

Zehaf-Bibeau then ran inside the Parliament, where he opened fire before he was shot dead by the House of Commons Sergeant-at-Arms, Kevin Vickers.

Politicians have now returned to the city's Parliament Hill complex, where Mr Harper said the Canadian government would 'be vigilant' to threats but 'not run scared'.

'We will always stand together,' Mr Harper said, vowing to push on with tougher security laws.

'They need to be much strengthened, and I assure you, Mr Speaker, that work which is already underway will be expedited.'

Harper was in parliament when the attack began, addressing members of his party on the increased terror threat to Canada.

In a televised address to the nation, he said: 'We will not be intimidated. Canada will never be intimidated.'

MPs applaud Kevin Vickers, Sergeant-at-Arms, who shot the gunman Michael Zehaf-Bibeau on Wednesday

Zehaf-Bibeau fatally shot Corporal Nathan Cirillo, a 24-year-old father, as he stood guard at the memorial

'This week's events are a grim reminder that Canada is not immune to the types of terrorist attacks we have seen elsewhere around the world,'

'We are also reminded that attacks on our security personnel and our institutions of governance are by their very nature attacks on our country, on our values, on our society, on us Canadians as a free and democratic people who embrace human dignity for all.'

One source told the Globe and Mail that MPs had flanked the doors of their meeting room, preparing to attack the gunman with sharpened flagpoles.

'These guys were up there holding these spears ready to impale anyone who came in,' the source said.

A man identified by Royal Canadian Mounted Police as Michael Zehaf-Bibeau is seen October 22 as he exits a car and runs toward the parliament buildings

Cirillo is raced to an ambulance after he was fatally shot in the abdomen by a gunman as he stood guard at the National War Memorial

Ottawa police said there were shootings at the War Memorial and at the Canadian Parliament

Mr Harper was placed in a cupboard - described as little more than a 'cubbyhole' in the Centre Block after the gunfire rang out, the report said.

The Globe and Mail's source said many MPs had no idea the prime minister was still in the building.

Foreign Minister John Baird said there were no substantiated claims yet that Zehaf-Bibeau was associated with Islamic State.

He said he was 'tremendously concerned about the number of Canadians who are radicalised and are fighting in Syria or Iraq, but we don't have any evidence to link the two at this stage'.

'Reports suggest that well in excess of 100 Canadians have gone to fight jihad in the Middle East and that's a huge concern.'

Mr Baird also said Zehaf-Bibeau could have done much more damage than he did.

'For several minutes it was complete horror, complete terror, we didn't know whether the door was going to be kicked in, whether there was one or a group of people.'

Canadian Prime Minister shakes hands with Sergeant-at-Arms Kevin Vickers who has been hailed a hero

Canada's prime minister vowed the country would "not be intimidated" after a reported Muslim convert stormed parliament and killed a soldier



