EDGEWATER, N.J. (CBSNewYork/AP) — A New Jersey community is in mourning after authorities said a man shot and killed his wife and 8-year-old daughter before turning the gun on himself.

The bodies of Michael Stasko, Melissa Stasko and 8-year-old Mellie Stasko were found Friday night at the Windsor at Mariners Tower, a luxury high-rise apartment building in Edgewater, Bergen County prosecutor John Molinelli said.

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“We believe the shootings took place while both Mrs. Stasko and young Mellie were lying in the bed. Right now, that’s what we believe,” said Molinelli. “It is also possible that it took place while they were both sleeping.”

Authorities said a .45-caliber handgun with hollow-point bullets was found where 53-year-old watch salesman Michael Stasko shot and killed his 49-year-old wife and their daughter before killing himself.

Michael Stasko had a gunshot wound under his chin. His wife and daughter had been shot in the backs of their heads. The shootings could have happened as long ago as Tuesday or Wednesday, authorities said.

It wasn’t until late Christmas afternoon when a relative in Missouri called police, telling them the family of three was supposed to be in that state to celebrate the holiday around 1 p.m. He told them they never showed up and couldn’t reach them on their cellphones.

Molinelli said Mellie had just celebrated her eighth birthday on Tuesday.

“One always has to wonder what would possess anyone to do that — an innocent 8-year-old girl,” he said.

Right now, investigators are trying to figure out the motive. Molinelli said the family had no history with police and there’s no indication they had any financial or legal problems.

“We don’t know whether it was financial. We don’t know whether it was familial. We don’t know really perhaps what was going through Mr. Stasko’s mind for him to do this,” Molinelli said.

Michael Stasko ran his business out of their apartment, selling custom watches to law enforcement, CBS2’s Ilana Gold reported.

Residents told 1010 WINS’ Roger Stern they were stunned to learn of the murder-suicide.

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“It’s very sad. I mean, for the family, you know, it’s very, very sad,” said Ladro Larios of Edgewater.

“Shock, yea, plain shock,” said another woman.

“I don’t believe that, it’s unbelievable, very sad,” said another.

One woman who lives on the same floor said she had no idea the shooting took place right across the hall, CBS2’s Steve Langford reported.

“I heard nothing,” she said. “I heard absolutely nothing.”

“A towel or a blanket was used at the front of the weapon which would at least help to silence the sound somewhat,” Molinelli said.

Molinelli described the family’s apartment as “lovely” and “well kept,” with neatly wrapped presents underneath a Christmas tree.

“You see some cards and holiday cards,” Molinelli said. “It would appear from the 8-year-old’s standpoint she very much loved her father.”

Molinelli called the case “troubling.”

“It is always troubling when an 8-year-old child is murdered this way,” he said.

Counselors, psychologists and social workers plan to help Edgewater students cope with the murder-suicide when they return to school Jan. 4, school district officials said. District officials will be available this week to help parents as needed.

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