The attack took place in the evening when a rocket fired from the abandoned military base of al-Rashid in southeastern Baghdad landed near the suspension bridge in the zone, which houses some of the main Iraqi government offices and the US embassy, the media office of the Joint Operations Command said in a statement.

Iraqi security forces seized another rocket set for firing in the same launch area, the statement said.

No group has so far claimed responsibility for the attack, as the military bases housing U.S. troops across Iraq and the US embassy have been frequently targeted by mortar and rocket attacks.

More than 5,000 US troops have been deployed in Iraq to support the Iraqi forces in the battles against the Islamic State militants, mainly for training and advisory purposes.