Canadian Ambassador to Afghanistan David Sproule said Canada's military is working to keep Afghanistan from becoming a breeding ground for terrorism again. ((CBC))

Canada's ambassador to Afghanistan urged a crowd in St. John's to support the military mission, saying it's needed to ensure the county doesn't spawn "extremists and terrorists" that may threaten Canadians.

Ambassador David Sproule, who was speaking to students at Memorial University of Newfoundland on Monday night, said there are two good reasons to maintain a diplomatic and military presence in Afghanistan.

He said the more than 2,000 Canadian troops posted in that country are helping it rebuild after decades of war.

Sproule also said Canadians must help prevent Afghanistan from again becoming a breeding ground for "extremists and terrorists."

After al-Qaeda's attacks on the United States on Sept. 11, 2001, the Taliban government that then controlled Afghanistan let al-Qaeda leaderOsama bin Laden and other militants take refuge in the country — prompting an invasion by U.S.-led coalition forces that toppled the Taliban.

Canada began sending troops to the countryin early 2002, initially as part of the forces under U.S. command and now as part of a 37-nationcoalition under NATO.

"We have to ensure that the kind of threat imposed out of Afghanistan by the Taliban in partnership with al-Qaeda never again poses a threat to Canada," Sproule said.

Quit 'dirty war,' critic urges

However, Sproule's defence ofCanada'smission drew a mixed reaction in St. John's.

Among the critics was Elizabeth Rowley, a member of the Communist Party of Canada who travelled from Ontario to hearSproule speak.

She said she doesn't agree with the ambassador.

"We've actually engaged in a really dirty war that originated in the United States and Canadians don't support that," Rowley said.

"We should get out right now."