Canada has a new hero.

Parliament has reopened and given a hero's welcome to Sergeant-at-Arms Kevin Vicker.

He was the man who yesterday shot dead a gunman who went on the attack in Ottawa.

Applause rang out for something like five minutes as the guardian of the cradle of Canada's democracy, entered the debating chamber.

That was followed by a prayer, the national anthem, a moment of silence and a brief statement by Prime Minister Stephen Harper.

"We see across the world increasing places where the planet is descending into savagery and there are people who every day of their lives stand on guard for this country and for all of us."

The lone gunman whose name was on a terror watch list, killed a soldier and attempted to storm the Parliament before Vicker shot him dead.

NZ's security concerns downplayed

Meanwhile, a senior government minister is downplaying concerns as our Parliament has its security tightened.

Following yesterday's attack on the Canadian Parliament in Ottawa, all access to our Parliament Buildings in Wellington has been restricted to just two entrances.

Cabinet Minister Gerry Brownlee doubts there's a problem here.

"They will have had a thought process that says, 'let's be a little cautious here' and a minimum disruptions for people and over the next couple of weeks they'll be reviewed."

The New Zealand public is being assured the risk of terrorism remains low following the drama in and around Canada's parliamentary buildings in Ottawa.

Security's been heightened at the Beehive in response to the perceived threat the killing has created.But Director of the Centre for Strategic Studies Robert Ayson says the real threat from terrorism is more psychological.

"One of the important things about acts of terror is that it's not so much the number of people who die from them. It's the broader psychological impact and the fear they create."

Robert Ayson adds concerns our defence force is too small to cope with the threat are unfounded.

"I don't think that because of the small size of our defence force that we are therefore more vulnerable to more acts of terror. I've never felt that."

Ayson says while the extra security measures are prudent, a calm and measured approach to this threat of terrorism is needed.

"I wouldn't want people to think that because of this particular ISIS challenge at the moment that we should radically challenge our legislation and make massive increases in our security community, whether that's intelligence or other areas."