US forces have intensified their war against Iraqi cleric Moqtada al-Sadr today by sending tanks into Najaf's cemetery to attack militia positions among its ancient tombs for the first time.
Explosions and gunfire rocked the city for hours, and there was fighting around the main police station, less than a mile from some of the holiest Shia shrines.
Sadr aides showed journalists three holes in the gilded dome of the Imam Ali mosque, Najaf's most sacred spot, and blamed US shellfire. It was not clear what caused the damage.
Dr Jubayr Awdah Faysal told Al-Jazeera television people arriving injured at the city's general hospital spoke of wounded people lying in the streets and alleged US tanks were stopping ambulances from getting to them.
At least seven US tanks thrust deep into the cemetery, a city within a city covering several square miles where Shias from all over the world wish to be buried within sight of Najaf's sacred shrines.
Sadr's militia have been using the graveyard to stage hit-and-run attacks on US positions on the edge of town.
US commanders say they will try not to encroach on holy sites, including the Imam Ali shrine where Sadr has taken sanctuary.
When fighting died down in the afternoon, some 250 fighters of Sadr's Mehdi Army, some clad in black and most wearing Arab headscarves across their faces, paraded before the Imam Ali mosque chanting "Long live Moqtada!" and displaying assorted pieces of US military hardware.
Sadr himself was able to move out of town and preach his usual weekly service at Kufa, on the outskirts of Najaf.
There were also clashes between US-led forces and the Mehdi Army in nearby Kerbala, another holy Shia city. At least four Iraqis were killed and 13 wounded in overnight fighting, which has now died down.
In Baghdad, more than 300 Iraqi prisoners were released today from Iraq's notorious Abu Ghraib prison. The coalition periodically releases prisoners from Abu Ghraib on the western outskirts of the city.
Abuses by US soldiers at the jail have damaged the credibility of President George W. Bush's invasion of the country.
US Defence Secretary Mr Donald Rumsfeld went to Abu Ghraib yesterday and insisted the Pentagon did not try to cover up abuses there. He called the controversy surrounding the prison a "body blow for all of us" and said the people who did wrong will be punished.