NEWINGTON, Conn. (AP) _ Matthew Beck was a changed man when he returned to work at state lottery headquarters from a four-month, stress-related leave. The change was not for the better.

When the 35-year-old accountant came back Feb. 25, he wouldn't talk. He was mad at the world. He seemed paranoid. Some co-workers were afraid of him.

``He wasn't the same Matt,'' said Karen Kalandyk, his supervisor. ``He was like talking to a stone.''

On Friday, the stone crumbled.

About 30 minutes after reporting for work, Beck pulled out a semiautomatic handgun and began shooting his bosses. When he was finished, four supervisors were dead. He then killed himself.

Beck killed with a calculated coldness, first walking into the office of information services chief Michael Logan. He shot Logan and stabbed him with a butcher knife. He then shot chief financial officer Linda Mlynarczyk, 38, and Rick Rubelmann, 40, vice president of operations.

Then he chased lottery chief Otho Brown into a gravel parking lot.

Brown, 54, stumbled and fell on his back. He had his hands up and was begging ``Don't kill me, don't kill me,'' a law enforcement source said.

Beck told him, ``Aw, shut up,'' and shot him, the source said.

Moments earlier, Beck had walked into a room where Mlynarczyk, 38, sat waiting to meet with him. Kalandyk, who was in the room, said Beck raised his gun, pointed it at Mlynarczyk and told her, ``Bye, bye'' before shooting her three times.

Since his return to work, Kalandyk said, Beck's cold, aloof manner and his fascination with guns and paintball frightened some co-workers.

His personal problems began more than 18 months ago.

Beck, a Florida Institute of Technology graduate who had worked for state government for eight years, contended he got a bad deal in July 1996 when supervisors shifted him from number-crunching at the lottery agency to testing computer software. He wanted back pay, contending he should have been paid more for the computer job than his accountant's salary.

Beck, a former security guard, had a permit to carry a gun. Within the past year he had moved in with his father, who acknowledged his son ``had problems.''

A blue sticker on their front door reads: ``Warning: Trespassers will be shot. Survivors will be shot again.''

But Peter Donahue, a lottery accountant, said Beck gave no hint of his murderous plan when he showed up for work Friday.

``I saw him come in and hang up his coat,'' he said. ``He seemed OK when I saw him. It was just a typical day.''

Thirty minutes later, it was chaos.

Donahue was looking over lottery figures when he heard gunshots down the hall where Beck was scheduled to talk with his supervisors about his job.

Panicked lottery workers fled in all directions, hiding in a ditch, behind trees and in a storage room at an adjacent paint company. Beck chased Brown out of the building and into the parking lot.

Brown had gone about 100 yards from the building when he stumbled and fell, apparently after losing his left shoe.

``That's when Beck shot him,'' Donahue said. ``I hid my eyes. I couldn't watch.''

Beck shot himself seconds later, as police closed in on him, and fell just feet from his last victim. He died a short time later at Hartford Hospital.

Witnesses said Beck was a man on a mission.

``He didn't come in and just start blasting. He planned it,'' Donahue said. ``He was definitely after the managers.''