CHICAGO (CBS) — A Melrose Park police officer is in custody after allegedly shooting two people, one of them fatally, while off duty in Maywood this week.

Maywood Police Chief Valdimir Talley Jr. confirmed the Melrose Park officer was being held in police lockup, but he wouldn’t go into detail about the shooting, saying detectives have yet to interview the officer.

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Talley said Melrose officers were called to an apartment on Lake and North 5th Avenue on Tuesday night. Inside, they found two men who had been shot.

Arthur Walton, 33, was pronounced dead.

Matthew Carter, 25, had been shot in the leg, and is recovering at Loyola University Medical Center.

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Talley said the shooter identified himself as an off-duty Melrose Park officer.

Neither Maywood Police nor Melrose Park police have provided details about what led up to the shooting, or why the officer pulled the trigger.

Talley said Maywood detectives are interviewing witnesses before questioning the officer.

“It’s several reasons. One being that we need to make sure that we have all the factual information in place before we can ask him what went on,” Talley said.

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The Melrose Park Police Department said the officer is on paid administrative leave, but provided no further details about the deadly shooting.