ROME - Hundreds of people flocked to a Rome church today to pay their last respects to an Italian intelligence officer shot and killed by American troops in Iraq while escorting an ex-hostage to freedom.

The state funeral of Nicola Calipari in the Santa Maria degli Angeli church in downtown Rome was expected to draw the country's president, Carlo Azeglio Ciampi, and other top officials. U.S. Ambassador Mel Sembler was among those attending, news reports said.

The funeral came after Calipari's body lay in state at Rome's Vittoriano monument, with tens of thousands of people streaming past the flag-draped coffin since the body returned from Iraq on Saturday night.

Meanwhile, the hostage whose life Calipari saved said it was possible they were targeted deliberately because the United States opposes Italy's policy of negotiating with kidnappers.

Journalist Giuliana Sgrena, who was abducted Feb. 4 in Baghdad, was recovering in a Rome hospital from a shrapnel wound to the shoulder and was not expected to attend the funeral. Calipari was killed when U.S. troops at a checkpoint fired at their vehicle Friday as they headed to the airport shortly after her release.

Calipari was to be awarded a gold medal of valor for heroism. An autopsy was performed Sunday, and the Italian news agency ANSA quoted doctors as saying Calipari was struck in the temple by a single round and died instantly.

Sgrena said Calipari died shielding her. She offered no evidence to support her claim that the attack was deliberate, and in an interview published in today's edition of the daily Corriere della Sera, she said she doesn't know what led to the attack.

"I believe, but it's only a hypothesis, that the happy ending to the negotiations must have been irksome," she said. "The Americans are against this type of operation. For them, war is war, human life doesn't count for much."

Sgrena has rejected the U.S. military's account of the shooting, claiming instead that American soldiers gave no warning before they opened fire.

The White House called it a "horrific accident" and promised a full investigation.