US forces in the northern city of Mosul came under attack yesterday as insurgents fired rocket-propelled grenades at a military compound and a bomb exploded near a military convoy.No casualties were reported in the barracks incident, the US military said. Two Iraqi teenagers were slightly injured in the downtown explosion near Mosul's city hall, witnesses said.

　　Mosul, Iraq's third-largest city, had been relatively quiet in the past several months, but the security situation has deteriorated since October.

　　On Tuesday night, attackers struck at the center of the US-led occupation, firing mortars after sundown at the heavily guarded district that includes major American facilities. Three people were wounded, the Pentagon said.

　　Huge explosions thundered throughout central Baghdad about 7:45 pm as the insurgents targeted the 5-square-kilometer "Green Zone," which includes coalition headquarters, the military press center and other key facilities.

　　Iraqi police said two mortars fell in the zone, but US officials said the headquarters itself, located in one of Saddam Hussein's former palaces, was not damaged.

　　However, the huge detonation sent coalition staffers runningsintosthe hallways. It was the second mortar attack against the Green Zone in as many days.

　　At the Pentagon, a spokesman said three people were wounded in the attacks but it was unclear if they were military or civilians.

　　There appeared to have been three explosions, possibly from mortars or rockets.

　　The attack underscored the precarious security situation in the city. Late on Monday, three mortars exploded in the center of Baghdad. US officials said one struck a camp of the 2nd Armored Cavalry Regiment, which provides security in the palace district. Officials said there was no damage nor casualties.

　　The deteriorating security situation has prompted the United Nations, the international Red Cross and other international organizations to reduce their foreign staffs.

　　Spain became the third coalition member to withdraw diplomats from Iraq because of stepped-up insurgent attacks. Last month, Bulgaria and the Netherlands moved their diplomats to Jordan, also citing worsening security.

　　Those fears increased after a dramatic escalation in attacks.