EL PASO, Texas — A Mexican man in federal custody died at an Arizona hospital Monday morning, U.S. Customs and Border Protection officials said in a news release.

Border agents from the Border Patrol’s Tucson Sector apprehended the 49-year-old man about 1 p.m. Sunday in an area south of Casa Grande, Arizona. 

While processing him, agents determined the man needed medical attention and took him to a hospital in Tucson. There, medical staff learned that man had a pre-existing heart condition.

CPB said the man died about 9 a.m. Monday at the hospital, though the cause of death is not yet known. It’s unclear how long the man was in custody before he was taken to the hospital. 

In a statement, CBP offered condolences to the man’s family, saying the agency is “saddened” to report the man’s death.  

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