Hialeah police say the cause of a deadly accident involving one of their own detectives was a blown stop sign.

On-duty detective Raul Somarriba plowed into the black Jeep Compass driven by Marcos Barrios after Barrios ran a stop sign at East Ninth Court and East 49th Street Friday night, police spokesman Carl Zogby said Tuesday.

Zogby said that, based on the current evidence, police do not think the detective was speeding. But the force of the crash flipped the Jeep upside down and sent Somarriba’s unmarked car flying over a median.

Barrios and passenger Andrea Castillo, 21, weren’t wearing seatbelts, Zogby said. Castillo, the daughter of new Miami-Dade School Board member Susie Castillo, was declared dead Sunday afternoon and was kept on life support for organ donation.

Zogby said the detective endured a 10-hour operation Tuesday and faced the possibility of “long-term disability.” Somarriba suffered a fractured leg and arm, and head injuries. He was the only person airlifted from the crash.

Hialeah Fire Department spokesman Cesar Espinosa said the decision to airlift the detective and not Castillo didn’t contribute to “patient outcomes.”

“The mode of transportation chosen for all the patients was appropriate, expeditious and provided the highest quality of care,” Espinosa said.

“Air rescue transported the police officer because he met the highest degree of severity in injuries at the time.”

Zogby said Barrios, whose age was not released, was in stable condition.

“He’s going to come along fine,” Zogby said.

Jorge Silva, an attorney representing the Castillo family, challenged some of the statements made by Hialeah police.

He said that Andrea Castillo had bruises that suggest she was, in fact, wearing a seat belt, and questioned how police knew Barrios ran a stop sign if police had not even questioned him.

Zogby said police collected surveillance and talked to witnesses that prove that he did.

Silva also took issue with the fire department’s assertion that Castillo’s care was not affected because she was taken to the hospital by ambulance rather by helicopter.

“There is a dramatic difference, and the dramatic difference is timing,” he said, when a patient is airlifted.

Silva also said there were 40 yards of skid marks at the accident scene that suggest the detective was speeding.

The attorney said the Castillos want Hialeah police to step aside and allow another department to investigate the accident.

“This family is absolutely and utterly devastated, and they have a lot a lot of questions and not a lot of answers,” he said.

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