Canada has taken command of the force of international peacekeepers in charge of maintaining security in Afghanistan's war-battered capital.

Canadian Brig.-Gen. Peter J. Devlin assumed command of the Kabul Multinational Brigade in a ceremony at the brigade's headquarters Thursday.

The job of the Kabul brigade, which is part of the larger International Security Assistance Force (ISAF), is to "assist the Afghan security forces and provide a secure environment for the re-establishing of community structures in Kabul and its surrounding areas," ISAF commander Lt.-Gen. Norbert van Heyst said in a prepared statement.

The 3,600-strong brigade currently has 350 Canadian troops, but the Canadian contingent will expand in August to about 1,800 troops, including three rifle companies from the 1st and 2nd Battalions, and Royal Canadian Regiment.

They are scheduled to start patrol on Aug. 21.

With rebels and Taliban loyalists continuing to stage attacks on the peacekeepers, as well as against government targets, the job is a dangerous one. Most recently, four German troops died when an explosive-laden car rammed into the bus they were riding to the airport.

In all, about 20 NATO-led troops have been killed in what have become weekly attacks.

Defence Minister John McCallum acknowledged on Thursday that the mission is far more dangerous than the typical United Nations peacekeeping operation. He said Canadians are prepared for casualties among their soldiers.

"We all hope that there will not be," the defence minister said. "But if it is critical to the security of our country... Canadians would accept the inevitability of it.''

Before he left for Kabul on Saturday, Devlin said mission is one of the most dangerous and volatile of the five he has been on.

"This is different because Afghanistan is one bullet away from trouble," he said. "It's a combination of the country and its horrible infrastructure, tremendous poverty and a young government that is working very hard to establish control and democracy throughout a nation.

"There is potential for organizations to feed on the poor state of the country's infrastructure and poverty to counter (those efforts)."

Some military officials have estimated that between five and 10 Canadian soldiers will be killed on the Afghan deployment.

With a report from The Canadian Press