FACTBOX: Security developments in Iraq, April 21

(Reuters) - Following are security developments in Iraq at 2000 GMT on Monday.

* TIKRIT - Two U.S. soldiers were killed by a roadside bomb in Salahuddin province, the U.S. military said. Two other U.S. soldiers, two Iraqi security volunteers and a civilian translator were wounded.

* BASRA - A local councilor in a town near the southern city of Basra was assassinated in front of his home by unknown gunmen, police said.

* MOSUL - A roadside bomb struck a police car in the northern part of the northern city of Mosul, wounding two policemen, police said.

* BASRA - Iraqi forces arrested a gang responsible for kidnapping and killing doctors, clerics and women in Basra, said Interior Ministry spokesman Major-General Abdul-Karim Khalaf.

* MUSAYYIB - A U.S. drone aircraft crashed near Musayyib, south of Baghdad, and was recovered, the U.S. military said.

* BAGHDAD - Four bodies were found around the capital on Monday.

BAGHDAD - U.S. forces killed three militants on Monday morning who had shot a rocket-propelled grenade at their patrol in New Baghdad in the southeast part of the capital, the U.S. military said.

BAGHDAD - A U.S. drone aircraft fired a Hellfire missile at three heavily-armed militants in Sadr City, east Baghdad, on Sunday night, killing all of them, the U.S. military said.