Iraqi officials say a suicide bomber on a bicycle has killed at least 29 people at a police base in Baquba, north of Baghdad.
The bomber struck Monday morning as police recruits gathered for a training session. Twenty other people were wounded in the attack. Baquba is the capital of Iraq's Diyala province, where Sunni Arab tribesmen and militants have joined U.S. and Iraqi forces in fighting al-Qaida in recent months.
In other developments, Iraqi officials found 20 headless bodies dumped near Baquba.
Meanwhile, the Iraqi defense ministry says a group of sheikhs from Diyala who were kidnapped Sunday have been freed. Defense ministry spokesman Major General Mohammed al-Askari did not provide further details. The sheikhs were kidnapped in Baghdad after they met with a government official. Also, the U.S. military handed over security responsibilities in the mostly Shi'ite province of Karbala to Iraqi authorities. It is the eighth of Iraq's 18 provinces returned to Iraqi security control.