The blasts hit a security checkpoint at Baghdad's Green Zone[REUTERS]

Two car bombs have exploded near an entrance to Baghdad's fortified Green Zone, killing five people and wounding at least 22 others, security sources said.

Monday's blasts occurred near a security checkpoint at the western entry of the Green Zone, where government buildings and foreign embassies are located in central Baghdad.

An interior ministry source said the casualties include Iraqi soldiers.

But a doctor at Al-Yarmuk hospital said they had so far admitted 13 people with injuries.

Qassim al-Moussawi, Baghdad security spokesman said the blasts occurred about 150 to 200 metres from the western gate of the Green Zone, an area frequently targeted by mortar and rocket attacks by insurgents.

"The two cars have burned. They were queuing in a line to enter the Green Zone," he said. "It's possible they were carrying either roadside bombs or they were packed with explosives and driven by suicide bombers."

A separate attack involving two roadside bombs in the upscale residential neighbourhood of Jadriyah in east Baghdad left five more people wounded, three of them members of the security forces, the interior ministry official added.

Violence has fallen sharply in Iraq in recent years but armed fighters still carry out daily attacks.