The deputy mayor of Kandahar, Afghanistan, was assassinated Monday as he took part in evening prayers, according to a local government spokesman.

Azizullah Yarmal, 45, was praying in a mosque in the Sadoza Dana neighborhood around 9 p.m. when at least one attacker walked in and shot him in the back of the head, Zalmai Ayoubi, a spokesman for the Kandahar government, told CNN. He called it a "brutal attack."

Ayoubi said police have sealed off the mosque and are investigating the killing.

Also in Kandahar on Monday, a donkey-towed cart loaded with explosives and a remote control detonator blew up at a police post, killing at least three people and wounding four, officials said.

Ayoubi said three children were killed by the blast, and two police and two civilians were slightly wounded.

Read more at CNN.com's Afghanistan Crossroads blog