Baghdad: Three US soldiers have died after suspected militants attacked the heavily-fortified Green Zone and another base in Baghdad, according to the US military.

The rocket attack on the Green Zone, which contains government offices and embassies, killed two US personnel and wounded dozens.

Meanwhile a separate attack at a base in the Rusatmiya district killed another soldier.

The attacks came as Iraqi forces backed by US troops engaged in heavy fighting with Shiite militiamen in Baghdad’s Sadr City. At least 16 civilians died in the fighting.

Shiite cleric Moqtada Al Sadr has called for a mass rally to protest against the US military operations.