SAN ANTONIO - Story updated Thursday at 4:13 p.m.:
The victim was identified as Tammy Deseray Martinez, 24, the Bexar County Medical Examiner's Office said.
A 24-year-old woman who was found dead Wednesday morning in a West Side field about 30 feet from the wreckage of her SUV apparently had been there for some time before anyone noticed, San Antonio police said.
The woman's body was covered in frost when officers discovered it after 6:30 a.m. in a grassy area near a Highway 151 access road and Pinn Road.
"It looks like she's been here for a few hours," said Sgt. Michael Guzman, of the San Antonio Police Department. "People that passed by, saw the car overturned in the field and alerted us."
Guzman said it was still dark outside when the passersby noticed the car.
He said those people checked the vehicle for victims, but did not see anyone.
Only after daylight, and after officers and firefighters arrived, was the woman found.
She already was dead, apparently ejected from the vehicle and not wearing a seatbelt.
"We have no idea how it happened, how fast she was going. That's what our investigative unit will figure out," Guzman said.
Police did not find any witnesses to the crash right away.
But, Guzman said it appears the woman was driving on the access road when she lost control of her vehicle for some reason.
Police found child safety seats inside the SUV, so they had their helicopter fly over the area to look for any other possible victims.
Guzman said they did not find anyone else, and it appears the woman was alone when she crashed.
He said it also looks as though her vehicle was the only one involved in the crash.
During the investigation, police closed the westbound Highway 151 access road between Callaghan and Pinn roads.
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