Baghdad- Three policemen on Tuesday were killed and seven injured in a blast that ripped through downtown Baquba city, according to a security source.

A bomb was detonated inside a popular restaurant in front of Diyala's police department in downtown Baquba city, the source told Voices of Iraq news agency.

Baquba, the capital city of Diyala province, lies 57 km northeast of Baghdad. (dpa)