UPDATED 09/09/11 12:34 p.m.
CHICAGO (CBS) -- Police are investigating after a man in custody hanged himself at the Grand Central Area station on the city's West Side.
Guillermo Villamil, 49, of the 6200 block of West Diversey Avenue, was hanged in the Grand Central District station lockup at 5555 W. Grand Ave., according to the Cook County Medical Examiner's office.
Villamil was discovered hanging by his own shirt in the lockup during a routine check of the cells, according to police News Affairs Officer Robert Perez.
The lockup keeper who found Villamil cut him down and performed CPR on him until the Fire Department arrived and transported him to Our Lady of the Resurrection Medical Center, Perez said.
He was pronounced dead at Our Lady of the Resurrection Medical Center at 9:25 p.m., according to the medical examiner's office.
He had been arrested on a felony retail theft charge after allegedly stealing from a grocery store, sources said.
A death investigation is underway.
The Sun-Times Media Wire contributed to this report.
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