San Marcos PD, Texas Rangers investigating in-custody death after I-35 incident

SAN MARCOS, Texas (KXAN) — The San Marcos Police Department and Texas Rangers are investigating an in-custody death after an incident Tuesday evening, according to a Wednesday release.

Police responded to multiple 9-1-1 calls regarding a man on Interstate 35 near mile marker 200. Numerous callers said the man — described as white and in his 40s — was "acting erratically," yelling and possibly throwing objects while on top of the overpass over Posey Road. The man was identified as Dennis Thornton, a 43-year-old Leander resident.

San Marcos PD said when officers approached Thornton, he initially didn't respond but then began moving toward officers. Officers used a stun gun on Thornton, who then fell to the ground, per the release.

Police said there was a brief struggling while restraining and handcuffing Thornton, adding he "did not coherently respond verbally to questions or commands." Officers said they thought he might be having a medical emergency and took him to Christus Santa Rosa Hospital, where he died.

The Travis County Medical Examiner's Office has been tasked with completing Thornton's autopsy. San Marcos PD's Criminal Investigation Division, the department's Office of Professional Conduct and the Texas Department of Public Safety's Texas Rangers Division are investigating.

San Marcos PD will hold a press conference on Thursday at 9 a.m. to discuss the incident.