BAGHDAD, 16 August 2004 — US troops in armored vehicles and tanks rolled back into Najaf yesterday and new fighting broke out after truce talks collapsed a day earlier. The fighting resumed hours after Iraqi authorities warned journalists to clear out of the embattled city.

Najaf police chief Ghaleb Al-Jazaeri told a news conference all media should leave by noon, saying he would not be able to guarantee their safety after the deadline passed.

Police fired shots in the air, then arrested an Iraqi journalist working for Iran’s state-run Arabic language television station as he was broadcasting from the roof of a house in Najaf, the channel said.

The channel, Al-Alam, identified the reporter as an Iraqi called Mohammad Al-Kazem.

A group of policemen armed with rifles and pistols also went to a hotel where foreign and Iraqi reporters were staying and told them to leave the city. “I have an order that all journalists must leave Najaf now. Anyone who does not leave will be arrested,” said a police lieutenant, who gave his name as Mohammed.

The new US offensive cast a pall over yesterday’s opening of the National Conference, a gathering of more than 1,000 delegates from across Iraq seen as a key step toward democracy in the country.

Hours after the conference opened, insurgents fired a barrage of mortars that hit a commuter bus station in central Baghdad, killing two people and wounding 17 others, according to the Health Ministry.

The barrage apparently targeted the capital’s Green Zone, the heavily protected neighborhood where the conference is taking place but instead hit the station, which was left littered with glass, shrapnel and blood.

The National Conference aims to give a broader spectrum of Iraqis a voice in the political process and increase the legitimacy of the interim government of Prime Minister Iyad Allawi, which is dependent on American troops and money even after the end of the US occupation. But the failure to put an end to uprising in the south by followers of Shiite cleric Moqtada Sadr —with the continued Sunni-led insurgency elsewhere — threatens to undermine the conference.

Dozens of explosions from tank shells and mortars as well as constant small arms fire shook Najaf’s vast cemetery, where fighters from Sadr’s Mehdi Army have been battling US troops amid the tombs since the violence first broke out there on Aug. 5.

Before the fighting resumed, Interior Ministry spokesman Sabah Kadhim said: “A major assault by forces will be launched to bring the Najaf fight to an end quickly. I do not think there is an option as this matter has to be brought to conclusion as fast as possible and we want to bring the situation to normalcy soon.”

The government also showed footage of three foreigners seized for fighting alongside the Mehdi Army, as well as a cache of what it said were Iranian weapons. The footage of three men, who identified themselves as an Iranian, an Egyptian and a Jordanian and admitted fighting, was shown to reporters at a Baghdad news conference by Minister of State for Provinces Wael Abdul Latif.

Also in Baghdad, a roadside bomb killed a US soldier hours before the conference began. At least 931 US service members have died in Iraq since March 2003.

— Additional input from agencies