FACTBOX-Security developments in Iraq, May 10

(Reuters) - Following are security developments in Iraq at 1700 GMT on Thursday:

* denotes new or updated item.

* FALLUJA - A U.S. marine was killed in combat in Anbar province on Wednesday, the U.S. military said.

* BAGHDAD - Iraqi special forces, backed by U.S. troops, captured three suspects believed to be involved in a bomb attack that destroyed Baghdad's Sarafiya bridge last month, the U.S. military said.

DUBAI - The self-styled Islamic State in Iraq, an al Qaeda-led militant group, posted a video showing the killing of nine abducted Iraqi police and army officers, after an ultimatum it gave to the Iraqi government expired.

ANBAR PROVINCE - U.S. forces killed one insurgent and detained two others during raids in Anbar Province while targeting a chemical bomb network and smuggling operations, the U.S. military said.

NEAR RAMADI - Iraqi police cleared al Qaeda militants from a town near the city of Ramadi, 110 km (68 miles) west of Baghdad, police colonel Dawud al-Faraji said. They arrested 56 insurgents, seized 950 passports and found a mass grave.

BAGHDAD - The Iraqi army killed two insurgents and arrested six others during the past 24 hours in different parts of Iraq, the Defense Ministry said.

BAGHDAD - Police said they found the bodies of 21 people shot dead in various districts of Baghdad on Wednesday.

MOSUL - A hospital received the bodies of three people, two women and a man, from one family in the northern city of Mosul, 390 km (240 miles) north of Baghdad, police said.

MOSUL - The bodies of two police officers were found in Mosul, police said.

MAHAWEEL - The bodies of two people shot and tortured were found in the town of Mahaweel, 75 km (50 miles) south of Baghdad.

ISKANDARIYA - A roadside bomb wounded five people on Wednesday in the town of Iskandariya, 40 km (25 miles) south of Baghdad, police said.

BAGHDAD - U.S. forces killed three insurgents and detained four others suspected of being involved in the smuggling of weapons from Iran into Iraq during raids in the Sadr City district of Baghdad, the U.S. military said.

HAWIJA - Gunmen killed a policeman while he was heading to work in the town of Hawija, 70 km (40 miles) southwest of Kirkuk, police said.