BAGHDAD, Iraq, April 30 - The car carrying the Italian journalist Giuliana Sgrena that was struck with a deadly hail of gunfire as it sped toward Baghdad International Airport on March 4 ignored warnings from American soldiers who used a spotlight, a green laser pointer and warning shots to try to stop it as it approached a checkpoint, the American military said in a report released Saturday evening. The gunfire killed Nicola Calipari, an Italian intelligence agent who was in the back seat with Ms. Sgrena. The driver and Ms. Sgrena were wounded. Lt. Gen. John R. Vines, the ground...