An investigation is underway after a 49-year-old inmate at the Carrizalez-Rucker Detention Center died Saturday.

Jose Sergio Valdez was hospitalized after collapsing in the prison on Friday, according to the Cameron County Sheriff’s Office.

“Security footage showed Valdez exercising Friday evening, then sitting down and within minutes slumping over and falling face down,” the sheriff’s office stated in a news release.

Valdez was transported to a local hospital where he passed away the following morning.

A preliminary report attributed Valdez’s death to a brain hemorrhage, the sheriff’s office stated, adding that an autopsy was ordered.