SAN ANTONIO – A man charged in a deadly double shooting outside a Southside San Antonio grocery store died Tuesday evening while in custody at the Bexar County Jail, authorities said.

Lorenzo Aleman, who was facing a capital murder charge in the deaths of his ex-girlfriend and her new partner, was pronounced dead just before 5:45 p.m., according to a statement from the Bexar County Sheriff’s Office. No further details about the circumstances of his death have been released.

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Aleman, 53, was arrested early Monday, hours after police say he shot and killed 41-year-old Beatriz Guzman and 31-year-old Jeronimo Aleman Ramirez in the parking lot of an H-E-B Plus on South New Braunfels Street, shortly before 11 p.m. Sunday.

According to investigators, Aleman approached the couple and opened fire before driving off. Guzman and Ramirez were both pronounced dead at the scene. Aleman was taken into custody less than five hours later.

Authorities said Aleman and Guzman had previously been in a romantic relationship, and that Ramirez was Aleman’s nephew.