SANTA ANA — In the way that parents do, her father had warned her repeatedly about traveling to Mexico.

"Don't go down there," he would say. "The roads are dangerous."

But Rosemarie Maldonado, 21, a promising UC Irvine premed student, always went anyway.

Maldonado died Saturday after the vehicle she was in tumbled down an embankment near the Baja California border town of Tecate, her family said Monday. She and a group of friends, part of a students' group known as the Flying Samaritans, had gone to Mexico to participate in a medical clinic at El Testorazo, about 27 miles south of the border.

"My sister's whole life was planned for a medical career," said Mary Alice Maldonado, 29, of Santa Ana. "She was a volunteer at convalescent homes since she was in grade school and although my father always warned her about how dangerous Mexico is, she would always go with the Flying Samaritans to Mexico.

"It's ironic that she was going down to provide the medical services that Mexico needs and finds herself a victim."

A spokesman for the San Diego County coroner's office said the driver of the vehicle, Kelly Brae, another UCI premed student, apparently hit loose sand on the paved road, tried to brake and lost control of the vehicle.

Maldonado, who was not wearing a seat belt, was one of two students thrown from the vehicle, a coroner's spokesman said. The other student, Amanda Fox, was treated and released Monday from University Hospital in San Diego after being airlifted there by a Sheriff's Department helicopter.

The vehicle was carrying five students, including Fox and Maldonado.

Michael Farner, 21, a UCI premed student who was in another car when the accident happened, said the victims were taken to a clinic in Tecate in the back of a pickup truck.

Both victims were later transported to a second clinic because the first did not have the capability to treat Maldonado's injuries, Farner said.

"They had a doctor at the second clinic, but she was suffering from multiple blunt trauma and needed surgeons and a whole team of doctors," said Farner, who then made arrangements to take her to the border entry point in Tecate, where she could be airlifted to a San Diego hospital.

"We wanted to make arrangements for a life flight so the helicopter would land on the U.S. side. But the helicopter didn't come because it was fogged in at the San Diego airport," Farner said.