Although Canada sees no immediate danger for its citizens in the wake of a series of fatal attacks in London on Thursday, the nation has entered a state of heightened vigilance.

"Let's be clear, Canada is not actively the object of any terrorist threats," Prime Minister Paul Martin said Thursday from Gleneagles, Scotland where he's attending the annual G-8 summit. "But we have to increase our vigilance and this is what we've been doing."

Right after news of the London terrorist attacks reached Canada, the country's 24-hour emergency preparedness system kicked in, said officials.

Earlier Thursday, Deputy Prime Minister Anne McLellan said Ottawa has received no information about a threat of an attack on Canadian soil.

"But you have to be prepared," she said at a noon news conference in Edmonton. "You have to take all precautionary measures."

Canada is one of five countries listed by al Qaeda as possible targets. Thursday's co-ordinated bombing attacks were carried out by al Qaeda, according to a report. But that report has not been verified.

Canada and Italy are the only two countries on an al Qaeda hit list that have not yet been attacked. And while a terrorist threat may seem distant for many Canadians, the country's spy agency, CSIS, says there are at least 50 terrorist groups operating in the nation.

Sen. Colin Kenny, the chair of the Senate Committee on National Security and Defence, has warned about terrorist threats in Canada for years.

"It's not if it is going to happen. It's when it is going to happen," he says, adding that Canada should treat the London bombings as a wake-up call.

"The Canadian public is feeling very relaxed. When your intelligence people are saying there are 50 organizations in the country, you have reason to be concerned," Kenny told CTV.

Chief of Defence Staff Gen. Rick Hillier agrees.

"We are going to be threatened and at some point in the future, somebody will probably attempt to prosecute attacks here in Canada," he says.

While federal officials say Canada is prepared to handle a terrorist attack, Martin points out that all nations are vulnerable.

"We know very well that all countries are targets. And what's happened here in London could happen anywhere," he says.

The cabinet committee on public safety and security met on Thursday and discussed Canada's preparedness for an attack with key agencies and departments across the country.

The committee, along with McLellan, includes Defence Minister Bill Graham, Foreign Affairs Minister Pierre Pettigrew, Transport Minister Jean Lapierre and Health Minister Ujjal Dosanjh.

As of Thursday night, there are no reports of Canadian deaths or injuries in Thursday's bombings in London's Underground.

Canadians worried about relatives in London should call the Dept. of Foreign Affairs in Ottawa: 1-800-606-5499