The bus carrying 55 people from Houston to Missouri may have blown a tire, but officials were still investigating. Ten people were airlifted and the rest of the passengers were taken to hospitals by ambulance, many with serious injuries, said Fire Chief Jeff Jones.
"I saw crushing wounds, but there were very few walking wounded," he said.
The bus smashed into a guard rail at about 12:45 a.m. on a bridge that's about 15 feet above a creek, apparently skidding along the guard rail before sliding off U.S. 75 just the other side of the bridge.
"There were people deceased from the front of the bus to the back of the bus," said Officer Zachary Flores, one of the first on the scene, told The Dallas Morning News.
The bus came to a rest on its right side in the northbound lane of an access road. Workers righted the bus early Friday -- revealing a crumpled right side -- and loaded it onto a large flatbed truck. Other workers were cleaning debris and gathering luggage, shopping bags and scattered pieces of clothing.
"Please pray for us," said Holly Nguyen, a 38-year-old church member who was following behind the bus in a car but didn't see the wreck. She was anxiously waiting for word on whether her father, who was on the bus, was dead or injured.
Ayers said investigators have interviewed the bus driver and he is in stable condition. It's not believed that alcohol was a factor in the crash, Ayers said.
It was unclear if weather played a role in the wreck, but a National Weather Service meteorologist said there was some light rain in the area around midnight.
Police say 12 people died at the scene and another died at a Dallas hospital.
The injured, including the driver of the bus, were rushed to several North Texas hospitals. Many are in critical condition.
A spokeswoman at Wilson N. Jones Medical Center in Sherman said it was treating 15 patients, five of them in critical condition. A spokesman with Parkland Memorial Hospital in Dallas said three men and one woman were in critical condition.
The conditions of two women who were taken to Baylor University Medical Center at Dallas were being evaluated, a spokeswoman said. A man and a woman were in critical condition at Methodist Dallas Medical Center, a hospital spokeswoman said.
One person first brought to the Sherman hospital was transferred to Harris Methodist Fort Worth Hospital. That person's condition was not immediately known.
Northbound traffic on the highway was shut down as ambulances and helicopters used the roadway and median to ferry the injured to hospitals.
A Galveston/Houston archdiocese church official as saying many of those on the bus were from the Vietnamese Martyrs Church of Houston and were on their way to a religious festival honoring the Virgin Mary in Carthage, Mo.
Tinh Trinh, a member of the church for the past 20 years, said he was waiting to hear how one of his wife's friends was doing. "I myself cried this morning when I heard the news," said Trinh, one of only a few people at the large brick church early Friday.
The Marian Days pilgrimage, which started in the late 1970s in southwest Missouri, attracts thousands of Catholic Vietnamese Americans each year. Many attend a large outdoor mass each day while enjoying entertainment and camping throughout the city at night.
The accident was the worst bus wreck in Texas since 23 people died when a bus carrying nursing home residents fleeing from Hurricane Rita was rocked by several explosions after catching fire on a gridlocked highway near Dallas.
The wreck happened less than a mile from the spot where a trucker crossed the median and killed 10 people five years ago.
Sherman is about 65 miles north of Dallas.
If you need to get information on passengers on the bus, call 1-866-GET INFO
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