A man and woman pleaded guilty Monday to taking part in a smuggling scheme that resulted in the deaths of 19 illegal immigrants abandoned in a sweltering truck trailer.

Abelardo Flores (search), 34, and Fatima Holloway (search), 29, agreed to testify if needed at trials stemming from the nation's deadliest immigrant-smuggling attempt. They pleaded guilty to conspiracy charges.

They could get up to life in prison and a fine of $250,000 each, but prosecutors agreed to recommend lesser sentences. Sentencing was set for July 12.

Prosecutors said Flores recruited a New York man, Tyrone Williams, and paid him $7,500 to drive the tractor-trailer. Holloway was accused of being in the truck driving by Williams in May and lying at a border checkpoint when she told authorities the trailer was empty.

The trailer was carrying some 70 illegal immigrants from Mexico, Central America and the Dominican Republic being smuggled from the Rio Grande Valley to Houston.

The immigrants began to succumb to the heat and the trailer was abandoned at a truck stop in Victoria, 100 miles southwest of Houston, on May 14.

Seventeen immigrants were found dead inside the trailer and two others later died. The victims, including a 5-year-old Mexican boy, suffocated or died from heat and dehydration.

Fourteen people were indicted last year on charges of harboring and transporting illegal immigrants. Nine were arrested, and five remain fugitives.

The alleged ringleader, Karla Patricia Chavez (search), a Honduran woman, is set to go on trial in November.

Williams, the truck driver, is the only defendant in custody facing a death penalty if convicted. He is scheduled for trial June 7.