WESTMONT (CBS) — Police in west suburban Westmont said a 50-year-old man shot and a 6-year-old girl and her grandmother on Friday before taking his own life.

Police found the bodies of Mark J. Chapman, 50-year-old Linda E. Brennan and 6-year-old Julia A. Moore Friday morning in an apartment at 515 W. 61st St.

Officers were called to the apartment to conduct a well-being check at the request of family members.

A Saturday autopsy determined Moore and Brennan died of multiple gunshot wounds to the head, while Chapman died of a single gunshot wound to the head, according to the coroner’s office.

Police said Saturday “all evidence of Mark Chapman’s injury is indicative of a self-inflicted gunshot to the head.”

There was no sign of forced entry and police recovered the gun and a handwritten note, where Chapman said he alone killed Brennan, Moore and himself, police said.

Police have learned of an on-going custody dispute that may have contributed to the double-murder-suicide, the release said. The nature of the custody dispute was not indicated.

Westmont police Chief Thomas Mulhearn said the incident appeared isolated and reassured residents there is no danger.

“This was not a random act and involved only the three residents of the apartment,” Mulhearn said.

The Sun-Times Media Wire contributed to this report.

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