Three terrorist attacks Saturday across Afghanistan killed at least 20 people and wounded scores of others.

In the first incident, a suicide bomber rammed his explosives-laden car into a NATO convoy in the capital, Kabul, killing 17 people and wounding at least eight others. A NATO statement said five service members, eight civilian contractors and four Afghans were among the victims.

At least 12 of the dead are reported to be U.S. troops and employees, while Canada's defense ministry has confirmed that one of the dead was from Canada.

In a separate incident in southern Afghanistan, NATO said three service members were killed when an individual wearing an Afghan National Army uniform turned his weapon on Afghan and coalition forces. The shooter was killed in the incident.

And in Asadabad, the capital of northeastern Kunar province, a female suicide bomber wounded several Afghans before being killed outside government offices.

The Taliban has claimed responsibility for the attacks in Kabul and Kunar.

The commander of the NATO forces, General John Allen, condemned the attacks. He said those orchestrating such acts are doing it to “hide the fact that they are losing territory, support, and the will to fight.”

The U.S. Embassy in Kabul expressed deepest condolences to the families and friends of the victims and pledged to “continue their dedicated work on behalf of peace in Afghanistan and the whole region.”