BAGHDAD, Nov 24, 2008 (AFP) - At least 16 people were killed Monday in two separate bombings in Baghdad, including a blast caused by a female suicide bomber outside the heavily guarded Green Zone, security officials said.

In the first attack 11 people were killed when a roadside bomb exploded near a bus carrying trade ministry employees in a rush-hour attack in east Baghdad, security officials from the ministries of interior and defence said.

Less than an hour later a female suicide bomber blew up in a corridor leading into the Green Zone, where Iraqi employees were queuing and waiting to pass through the checkpoints leading inside, police said.

The entrance is at the start of a long, winding concrete maze with several checkpoints guarded by US and Iraqi forces and allied Ugandan soldiers.

The employees would have begun queuing in the early morning, with some waiting hours to pass through the layers of metal detectors, X-ray machines and body searches.

The Green Zone houses Iraq's parliament and several government offices and foreign embassies.

Iraq has seen significant improvements in security over the past year but bombings are still common in the capital and other restive areas.