A roadside bomb apparently aimed at a US military convoy exploded near hotels used by foreigners in central Baghdad early on Tuesday, but Iraqi police said there were no casualties. Overnight, resistance forces fired a dozen mortars or rockets in central Baghdad aimed at the Green Zone compound housing the interim Iraqi government and the US and British embassies. A series of strong explosions were also heard in Baghdad early on Tuesday, coming from the direction of the Sadr City neighborhood. In the Shiite Holy City of Najaf, fresh fighting broke out today, with explosions and gunfire coming from the heart of the city where Mehdi Army fighters loyal to Shiite Cleric Moqtada al-Sadr are dug in. Iraqi officials have reportedly given US military commanders permission to strike the Holy shrine in Najaf, where some members of the Mehdi Army are based. Meanwhile, news agencies out of the city say residents are rejecting a curfew and are vowing to fight the US forces. The LA Times reports today that the US has taken operational control” of Iraqi troops in the city.