The US troops staged a major assault on Iraq's holy city of Najaf early Thursday, following seven days of clashes with

Shiite Muslim militia led by Moqtada al-Sadr, the CNN reported.

The fighting broke out at around 7:00 am local time (0300 GMT).

The US military said on late Wednesday that it was preparing a final assault against the militia with the help of Iraqi forces.

Source: Xinhua