Baghdad/Mosul: Spokesmen for both the US and Iraqi military have confirmed that an eight year old girl strapped with explosives was the cause of a blast that killed an Iraqi captain and injured four soldiers south of Baghdad.

Iraqi Army Lt Ahmad Ali said the explosives were detonated yesterday as the girl approached the Iraqi commander in Youssifiyah.

Ali said from the scene that "the bomb was detonated by remote control, killing Capt Wassem Al Maamouri and injuring four soldiers."

He said authorities imposed a curfew and American troops are searching for those responsible.

Maj John Hall said US reports indicated one Iraqi solider was killed and seven wounded.

Meanwhile, Iraqi Prime Minister Nouri Al Maliki ordered a new assault on Al Qaida in the main northern city of Mosul yesterday, the jihadists' last urban bastion in Iraq according to US commanders.

Al Maliki travelled to Mosul with top aides to take command of the US-backed drive against Al Qaida in the province, defence ministry spokesman Maj Gen Abdul Kareem Khalaf said.

"Operation Umm Al Rabiain (Mother of Two Springs) has just started against those threatening the civilian population and attacking Iraqi forces in Mosul," defence ministry spokesman Khalaf told AFP.

"This operation is targeting terrorists and criminals," he said, alluding to Al Qaida, which has been accused of a string of major attacks across Nineveh province of which Mosul is the capital. Earlier this week, security forces announced a "new phase" in their operations in Nineveh, which borders both Syria and Turkey.

Officials said they advanced from the preparatory stage of the campaign to a full-scale offensive on Wednesday in a bid to flush out Al Qaida in Iraq.