The U.S. military in Iraq says at least six Iraqi policemen were killed in a car bomb explosion in the northern town of Tikrit Tuesday.

Officials say several policemen were also wounded in the attack believed to have been carried out by a suicide bomber.

Separately, at least seven people were killed in a small town south of Baghdad. The victims were passengers of a minibus passing through an area known as the "triangle of death."

The killings were the latest in a wave of attacks across Iraq, as insurgents pressed on with their campaign of violence ahead of the country's January 30 election.

Some information for this report provided by AP and Reuters.