FORT WORTH, Texas (AP) - The Latest on the death of a Texas sheriff's sergeant (all times local):

4 p.m.

Authorities say a Texas sheriff's sergeant who was found dead in his car suffered a medical emergency that caused him to fall and apparently strike his head.

The Tarrant County medical examiner's office determined Saturday that Sgt. Keith Shepherd suffered a pulmonary embolism.

After falling, he apparently was able to make it back to his car where he was found Friday evening by colleagues who searched for him when he didn't return from his break.

Deputies initially thought he had been shot, leading law enforcement personnel to swarm the area around the county jail in Fort Worth.

Shepherd was assigned to the jail and had worked for the sheriff's department for 19 years.

12:15 p.m.

Authorities say a Texas sheriff's sergeant has died after being found in his car "with significant injuries to his head."

Tarrant County Sheriff Bill Waybourn says Sgt. Keith Shepherd was found Friday night inside his personal car in a downtown Fort Worth parking lot. The parking lot is across from the county jail, where Sheriff's Department Chief of Staff David McClelland says Shepherd was assigned.

Deputies who found Shepherd initially reported that he had been shot, but Fort Worth police, who are leading the investigation, say there's no evidence that a shooting occurred. Authorities have not indicated how Shepherd suffered his injuries.

Shepherd had gone on break and colleagues searched for him when he didn't return.

Waybourn says Shepherd worked for the department for 19 years.

This report has been corrected to reflect that the sheriff didn't say the deputy had been shot.

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