LIVINGSTON, TEXAS (CBSDFW.COM/AP) — A Mexican man convicted of killing three teens in El Paso has died of apparent cardiac arrest.

A Texas Department of Criminal Justice spokesman says officials found 49-year-old Ignacio Gomez unresponsive in his cell Sunday morning. He was pronounced dead at an East Texas hospital about an hour later.

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Ignacio Gomez (Credit: TDCJ)

Ignacio had been on death row for more than 20 years.

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Gomez’s lawyer says he had been diagnosed with schizophrenia and found not competent to be put to death. He did not have a scheduled execution date.

Gomez was convicted in the 1996 shootings of 16-year-old twin brothers and a 19-year-old. He unsuccessfully challenged the conviction claiming police never told him he had the right to legal assistance from the Mexican consulate.

The consulate hasn’t commented on Gomez’s death.

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