UPDATED 04/11/12 6:13 p.m.

PALOS PARK, Ill. (CBS) – Authorities say a Palos Park man killed his wife, then turned the gun on himself Tuesday night in their southwest suburban home.

A teenage son found his parents, Wojiech “Walter” Puk, 53, and Larisa M. Markewych, 55, when he returned home from school around 6:30 p.m. Tuesday, authorities said. They lived in the 12300 block of Mohawk Road in Palos Park.

When police arrived at the home Tuesday, the couple was unresponsive.

An autopsy determined Markewych died of a gunshot wound to the head and her death was ruled a homicide, according to the Cook County medical examiner’s office. Wojiech also died of a gunshot wound to the head, and his death was ruled a suicide.

A family friend told CBS 2 that Markewych was a dentist, and Puk worked at a dental lab. They have a daughter who recently graduated from college, and a high school-age son.

A domestic dispute seemed to lead to the deaths. One police source says there was no forced entry into the home, and the firearm involved belonged to the husband.

Neither Puk nor Markewych has a civil or criminal court record.

(The Sun-Times Media Wire contributed to this report.)

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