By Jon Herskovitz and Lisa Maria Garza
AUSTIN, Texas (Reuters) - Four inmates and a corrections officer severely injured in a prison bus crash that killed 10 people in Texas remained hospitalized on Thursday as officials tried to determine what caused the vehicle to slide off the highway and slam into a moving train.
Three inmates were in critical condition and another was in serious condition at Medical Center Hospital in Odessa, a hospital official said. The guard, who was in critical condition, was transferred to a hospital in Lubbock, prison officials said.
The bus carrying 15 veered off an icy highway overpass and hit a moving freight train on Wednesday. Two correctional officers and eight inmates died from injuries suffered in the accident. The Texas Department of Public Safety said weather was likely to blame for the crash.
Only the bus driver had a seat belt and the rest of the passengers were seated on benches without safety restraints. Some were ejected from the bus, which she described as a minimum-security transport vehicle, said Sergeant Elizabeth Barney, a spokeswoman for the department.
The bus was traveling from Abilene to El Paso with 12 inmates and three corrections officers aboard. It was transporting prisoners from the Middleton Unit in Abilene, which houses male offenders and is not a high-security facility.
"The offenders were handcuffed right wrist to left wrist in pairs. This is standard procedure when transporting offenders. They were not handcuffed to the bus," said Robert Hurst, a spokesman for the Texas Department of Criminal Justice.
(Additional reporting by Jim Forsyth in San Antonio; Editing by Bill Trott)