SAN ANTONIO -- Hundreds of fans gathered at an Alamodome parking lot Monday night to pray for Tejano music star Emilio Navaira, who was critically injured in a bus crash and remained in a coma.

One woman said she had been waiting in the parking lot for six hours for the prayer vigil, while another woman said she had been there for four hours.

"Our prayers ... are for him," a woman, who clutched a large, framed picture of the San Antonio native, said.

One man said that he admires Navaira for his down-to-earth personality.

"(He's) good with people, the man said. "He talks with you like he's known you for a long time."

Among those who took the stage at the vigil were the singer's family members, including his brother, Raulito, who was injured in the crash.

Raulito Navaira promised the fans that their prayers will be heard.

"My brother's strong and stubborn, but he'll be back," he said.

Even if Emilio Navaira survives the severe head injury, the Grammy-winning artist faces a long recovery and an uncertain future, his doctors said.

The effects on his health "can be as bad as not surviving," said Dr. Alex Valadka, director of neurotrauma services at Memorial Hermann-Texas Medical Center and vice chair of neurosciences at the University of Texas Health Science Center at Houston.

They include a coma, vegetative state, weakness or paralysis, difficulty speaking, memory loss and inability to concentrate, Valadka said.

He put the survival rate for those suffering similar severe brain injuries at 30 to 35 percent.

The singer was among six people, all but one of them band members, aboard the bus and hurt in the crash on Interstate 610 in Bellaire, an enclave in Houston. They were returning home to San Antonio after playing at a Houston club Saturday night.

Police said while the crash remained under investigation, their preliminary probe showed Navaira was not licensed to drive the 26,000-pound bus. His agent said the singer loved to drive it and normally did.

The singer's blood will be tested for alcohol but the results likely wouldn't be known for a couple of weeks, he said. Also under consideration was the possibility that Navaira fell asleep.