Two U.S. pilots who mistakenly bombed Canadian troops in Afghanistan last year apologized to the families of the dead and wounded today as a hearing that could lead to their court-martial drew to a close.

The men expressed anguish over the accident, but they also defended their actions on the night of April 17, 2002, when the bomb killed four Canadian soldiers and wounded eight others near Kandahar.

Maj. Harry Schmidt, who dropped the 500-pound laser-guided bomb, called the accident a tragedy committed in the "fog of war."

Maj. William Umbach, the mission commander, began his statement by reading the names of the dead and wounded. "Since the seventeenth of April, not a day has passed that I have not thought of that night," he said.

"Major Schmidt and I were doing our best to protect ourselves in a situation where we honestly believed we were under attack," he said.

After the hearing, relatives of the victims met with reporters.

"I think Mr. Umbach felt very sincere, but Mr. Schmidt was trying to defend himself again. I had a hard time with that," said Claire Leger, the mother of Sgt. Marc Leger, 29, one of those killed.

Schmidt and Umbach are charged with involuntary manslaughter, dereliction of duty and aggravated assault. They could get as many as 64 years in a military prison if convicted.