FACTBOX: Security developments in Iraq, June 25

(Reuters) - Following are security developments in Iraq at 1500 GMT on Monday:

* denotes new or updated item.

* BAGHDAD - U.S. forces said they killed four members of a secret cell that brings sophisticated bombs into Iraq from Iran in a predawn operation in Sadr City in which a main battle tank destroyed a vehicle and troops called in an air strike.

BAGHDAD - Twelve people, including six Sunni tribal leaders, were killed and 18 wounded when a suicide bomber wearing an explosives-packed vest detonated inside a central Baghdad hotel, police said. A U.S. military spokesman put the death toll at eight.

BAIJI - A suicide bomber driving a fuel tanker killed 18 people and wounded 40 in an attack on a police headquarters in the oil city of Baiji, 180 km (110 miles) north of Baghdad, police said.

HILLA - A suicide car bomb attack near a governor's office killed eight people and wounded 31 in the city of Hilla, 100 km (60 miles) south of Baghdad, police said.

MOSUL - A car bomb killed three people and wounded 40 others in a residential street in Mosul, 390 km (240 miles) north of Baghdad, police said.

BAGHDAD - A U.S. soldier was killed by small arms fire in Baghdad, the U.S. military said.

BAGHDAD - U.S. soldiers killed three insurgents trying to place a roadside bomb in eastern Baghdad on Saturday, the U.S. military said.