Canadian forces and other NATO troops have been deployed to Kandahar after the main prison in the southern Afghan city was attacked by militants, who set most of the prisoners free.

Maj. Jay Janzen, a spokesman for the Canadian Forces, said troops were on the scene and had established a security perimeter in the vicinity.

"We believe the situation is under control," Janzen said, without elaborating.

Around 10 p.m., Taliban insurgents drove a car filled with explosives up to Sarposa prison's main gate and detonated it, destroying the gate and surrounding shops and killing 10 police officers in the vicinity.

Afghan officials also said Taliban insurgents fired several rockets at parts of the prison.

A Taliban spokesman said 30 insurgents on motorbikes and two suicide bombers attacked the prison. Qari Yousef Ahmadi also claimed that hundreds of Taliban prisoners were freed in the assault.

There were reports that 150 to 200 prisoners were still in the prison, with the rest having escaped.

But Wali Karzai, president of Kandahar's provincial council and the brother of President Hamid Karzai, said "all the prisoners escaped. There is no one left."

About 1,170 inmates were believed to have been in the prison and may now be roaming the streets of Kandahar city, Hunter said.

Canadian Forces are in command of Kandahar, and most of the roughly 2,500 Canadian troops in Afghanistan are stationed there.

The prison, the largest detention facility in Kandahar province, housed both common criminals and captured Taliban militants who had been fighting NATO troops and the Afghan government.

"It's a big blow. It's a very significant development," said CBC's Susan Ormiston, who visited the prison last April.

Suspected Taliban members detained by Canadian soldiers and turned over to Afghanistan officials are sent to the prison, located in the outskirts of the city.

Canada has spent $1 million on improvements to the facility, including new cell blocks and new windows.

Ormiston said Canadian officials were hoping the prison would become a model for other prisons in the region.

With files from the Associated Press