HOUSTON (AP) – As the temperature inside the airtight tractor-trailer soared to 173 degrees, the immigrants inside grew more desperate. Some clawed at the doors until their fingers were bloody; others crowded around a hole they had punched through the wall so they could breathe. Screams filled the tomblike box.

Then the bodies started falling in the darkness with a hard thud against the floor.

Truck driver Tyrone Williams, who prosecutors said ignored the immigrants’ cries as 19 of them slowly died, was convicted Wednesday of 38 counts of transporting illegal immigrants in the deadliest human smuggling attempt in U.S. history.

But he was spared the death penalty because the jurors could not agree on whether he bore direct responsibility for the deaths.

The judge also declared a mistrial on 20 counts of conspiracy and harboring after the jury deadlocked on those charges during 2½ days of deliberations. One of those charges also carried the death penalty.

Williams smiled and received congratulatory pats from his attorneys when he learned he would not face the death penalty. The 34-year-old could get life in prison.

Prosecutors said during the trial that Williams was paid $7,500 by a smuggling ring to carry more than 70 illegal immigrants from Harlingen to Houston in May 2003. The refrigeration unit on Williams’ trailer was not turned on for the trip.

Survivors testified that as the heat in the trailer became unbearable, the immigrants took off their sweat-drenched clothes and crowded around holes they punched out of the truck so they could breathe. They also kicked out a signal light to try to get the attention of passing motorists, and pounded on the walls.

One survivor said he used a cell phone to call 911 twice. The first call was answered in English. After he called back and got a Spanish-speaking dispatcher, no help arrived.

Prosecutors said Williams ignored the immigrants’ screams and banging and even called the operators of the smuggling ring on his cell phone to demand more money because he feared they would damage his truck.

Williams eventually abandoned the trailer about 100 miles southwest of Houston after opening the doors and finding some of the immigrants lying in the trailer. He was arrested a few hours later at a Houston hospital.

Seventeen people, including a 5-year-old boy, died inside the trailer of dehydration, overheating and suffocation. Two others died later.