LUBBOCK (CBSDFW.COM/AP) — A West Texas prison bus accident that killed two prison guards and eight inmates was likely caused when the bus hit a piece of displaced highway guardrail, sending the vehicle onto the center median and down an embankment, where it struck a passing freight train, according to a preliminary federal report released Thursday.
The National Transportation Safety Board report states that a 225-foot section of metal guardrail was damaged in an accident the day before the January 14 bus crash in Penwell, just west of Odessa. Accident investigators placed traffic cones in the area.
Two of three other accidents caused by icy road conditions on Interstate-20 on the day of the bus crash could have displaced the guardrail and pushed it into the path of the bus, the report states.
A witness traveling ahead of the bus told NTSB investigators that the damaged guardrail was about 2 feet into the lane where the bus was traveling, just before the bus reached the overpass where the accident happened.
The bus was in the left lane behind an 18-wheeler as it approached the section of guardrail and was passing a slower-moving 18-wheeler traveling in the right lane, the report states.
The bus, which traveled about 22 feet across an earthen median into an open area between the eastbound and westbound lanes, then went down a 21-foot embankment and became airborne, the report states. The vehicle hit the base of the embankment and continued forward toward the train.
The prisoners, who did not have seat belts, were handcuffed together in pairs.
Another guard and four other inmates who were seriously or critically injured in the accident are still recovering. The inmates are at prison medical facilities and the guard is at a facility in Abilene.
No one on the Union Pacific train, which was traveling below the maximum speed allowed for the area, was injured.
The bus had left a prison facility in Abilene about 4:40 a.m., bound for a prison in El Paso.
An email from the NTSB said the investigation was expected to be completed next year.
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