Unidentified insurgents kidnapped four Iraqi soldiers while they were on patrol in northern Iraq, police said on Thursday.

"Insurgents attacked an Iraqi army patrol by rocket-propelled grenades as it was on patrol late Wednesday near Siniyah town, wounding three soldiers and kidnapping four others with their military vehicle," Tikrit US-Iraqi liaison office said in a statement.

Iraqi police found the empty military vehicle Thursday morning near Siniyah, some 230 km north of Baghdad.

In Samarra, a policeman was killed along with his father when insurgents opened fire at their car, a medical source in Tikrit Hospital told Xinhua.

Insurgents have mounted attacks on Iraq's fledgling security forces and the newly-formed army in a bid to cripple the country's new government.

Source: Xinhua