HARRISON, N.Y. (AP) — A retired officer's suicide note indicates that the killing of his teenage daughters in their beds was a premeditated act, a suburban New York police chief said Monday.

Former White Plains Officer Glen Hochman had no known health or psychiatric problems and there were no indications of alcohol or drug use. Interviews with people who knew him, including former police colleagues, found no one had an inkling that "Mr. Hoffman would have committed this heinous crime," said Harrison police Chief Anthony Marraccini.

Nonetheless, "Harrison police investigators discovered a suicide note at the residence indicating that the killings were premeditated by Mr. Hochman," Marraccini said. The computer printout was addressed to his wife. The primary note was on the first page, followed by five or six pages of instructions on getting things in order.

The couple had discussed a possible separation in mid-January. She went to police on Friday to report a non-violent argument with her husband because a friend had urged her to document such incidents.

Alissa, 17, and Deanna, 13, were apparently both sleeping when they were shot in the head with their father's personal weapon, a 40-caliber Glock.

Their mother and older sister had gone to a Connecticut casino. The mother asked Alissa's teenage boyfriend to check the house because neither had been able to contact anyone there.

The boyfriend entered the garage at 3:36 p.m., found Hochman's body and called 911. Police found the girls' bodies. Three dogs also had also been shot to death.

"It's difficult, especially when you see two young girls, their lives have been ripped away, brutally murdered. You can't get any rationale for that," said Marraccini. "...The act is so incredibly bad."

Hochman spent 22 years at the White Plains Police Department before retiring recently. White Plains police Commissioner David Chong said Hochman had served with honor and integrity and the department was "shocked and horrified by the news of this unfathomable tragedy."