Delfina Guerrero Guerrero burst into tears Monday when she saw a crime scene photo showing the bruised face of her dead 18-year-old son, crying so loudly that prosecutors had to briefly stop questioning her.

"It's my son," the Mexican woman said after seeing Oscar Gonzalez Guerrero's photo, then began to sob again.

He was one of 19 illegal immigrants killed in the nation's deadliest smuggling attempt.

As Guerrero testified in the case of Tyrone Williams, accused of driving a truck with more than 70 illegal immigrants packed in the stifling trailer, several jurors also wiped away tears.

Guerrero was one of several relatives brought to Houston from outside the country to identify the victims. They were brought in because Williams went against his lawyers' advice and would not enter an agreement acknowledging the victims' identities and that they were in the country illegally.

Prosecutors had to fly in relatives of the 19 victims from Mexico, the Dominican Republic, El Salvador and Honduras to identify bodies from crime photos.

Juan Gonzalez Rivera, of Mexico, looked at a close-up photo showing the bruised and bloodied face of Ricardo Gonzalez Mata, 24, and began sobbing, wiping away tears with his jacket.

"How can I not recognize him? He was my son," he said.

Other victims' relatives stared at the floor or into the distance when they were shown the grisly photos of their loved ones.

Williams was driving the tractor-trailer during the 2003 smuggling attempt from South Texas to Houston. There was an air conditioning system in the trailer, but it was never turned on. Temperatures skyrocketed and the immigrants were forced to peel off their clothes and punch holes through the back doors for air as their body temperatures rose to as high as 113 degrees.

By the time the trailer's doors were opened and Williams abandoned the trailer at a truck stop near Victoria, about 100 miles southwest of Houston, 17 people were dead of dehydration, overheating and suffocation inside, and two more wouldn't survive.

Williams' attorney, Craig Washington, asked the victims' relatives whether their loved ones had health problems, such as a heart condition or high blood pressure. The relatives all said their loved ones were healthy.

Williams, 35, a Jamaican citizen who lived in Schenectady, N.Y., is the one of 14 people charged in the case who is facing the death penalty. So far, seven people have been sentenced to prison in the case. Sentencing for three others is pending. Charges against two were dismissed, and one man remains a fugitive.

A jury convicted Williams last year on 38 transporting counts, but a federal judge threw out the decision, saying it didn't count because the panel failed to specify his role.