BAGHDAD, Oct. 14 (Xinhua) -- A total of 12 Iraqi security members were wounded in a huge explosion at an ammunition depot of a military camp near the capital Baghdad, the Iraqi military said Monday.

The explosion occurred at the logistic support camp of the Explosive Ordnance Disposal (EOD) training center in al-Jaara area near the town of al-Madain in the southwest of Baghdad, the Interior Ministry Spokesman Saad Maan said in a statement.

"The incident resulted in the injury of an officer, six members of the EOD training center, four federal policemen and one member of the rapid reaction forces," Maan said, noting the investigation is underway.

A security source anonymously told Xinhua that the incident took place in the early hours of the day, when a series of explosions rocked al-Madain area and a fire broke out at the depot which provides logistical support to the Hashd Shaabi brigades, the federal police and the rapid reaction forces.

The explosions caused extensive damage to the camp, the source said, adding it was not clear what led to the explosions and the fire.

Iraqi security forces sealed off the area, while fire engines and civil defense personnel rushed to the scene to put out the fire, he said.

During the past few months, several similar incidents, believed to be caused by attacks by unknown aircraft, took place in Hashd Shaabi depots in central and western Iraq.