Afghan officials say two suicide bombers attacked police headquarters in the southern city of Kandahar Sunday, killing at least two police officers and wounding about 40 people.

Officials say the two bombers were inside the police building when they detonated their explosives. A police commander, Abdul Raziq was among the wounded, and officials say he may have been the intended target.

Earlier in the day, authorities said at least six people were killed in the attack.

A man who purportedly represents the Taliban told the French news agency that his militia was responsible.

In a separate incident in Kandahar today, a Canadian soldier was killed when his vehicle struck an explosive device in Panjwaii district.

And, in southern Afghanistan's Uruzgan province Sunday, a Dutch soldier was killed and five others were wounded in a roadside bomb blast.

Today's deaths bring Canada's military death toll to 97 and the Netherlands' toll to 17.

Also today, U.S. and Afghan officials say at least 20 militants died in two separate incidents.

Officials say U.S.-led forces in the eastern province of Khost killed at least 10 militants, while another 10 died in southern Helmand province during an assault on a police post.

Afghan police say another attack - on a NATO convoy in the western province of Herat - failed, after a suicide bomber exploded himself but failed to injure anyone.

Violence has surged in Afghanistan this year, as Taliban militants have stepped up their insurgency with suicide and roadside bombings.

Some information for this report was provided by AP and Reuters.