BRISTOL — Arthur Hapgood Sr. stepped outside 211 Park St. on Monday evening to smoke some marijuana, and when he returned, he was a changed man, witnesses told police.

He was making bizarre comments, waving his arms and yelling, and then started attacking people inside the house before fatally wounding a 1-year-old girl with a kitchen knife, a police report says.

Bristol police said Tuesday they suspect that the marijuana Hapgood smoked was laced with PCP or another powerful psychotropic drug. Hapgood "exhibited a state of mind that doesn't seem consistent with just marijuana use," said Bristol police Lt. Kevin Morrell. "We will be looking at any and all illicit drugs," he said, including PCP and formaldehyde, both of which are common additives to marijuana.

Hapgood told officers that he had "consumed illegal drugs" Monday evening, according to the report. When an officer asked him which drugs, Hapgood responded: "All of them."

Hapgood was staying at 211 Park St., his mother's house, because a day earlier he had been thrown out of the Waterbury home he shared with his wife, Estacy Riquelmy, and their children, according to the police report. His wife told police that Hapgood, 35, had punched her in the eye and mouth.

In Bristol on Monday night, Riquelmy and her daughter arrived at Hapgood's mother's house, where Hapgood was caring for the baby, and Riquelmy and Hapgood began talking about the previous night's events, according to the police report. Riquelmy's daughter was playing with the baby.

Hapgood was apologizing to Riquelmy just before he stepped outside to smoke the marijuana, according to the report.

When Hapgood returned, the couple began to argue "because he was talking strangely to her," Jeremy Hapgood, 19, told police. Jeremy Hapgood is Arthur Hapgood's nephew.

A moment later, Riquelmy called out to Jeremy Hapgood and his younger brother to grab Arthur Hapgood because he was "yelling wildly and waving his arms," the report says.

Arthur Hapgood was yelling, "Call my mother, call my mother," Riquelmy told police, because Hapgood's mother "is the only one who can control him when he's angry." At 7:18 p.m., a neighbor called 911 and police were dispatched.

"All you could hear [was] screaming," said the neighbor, Amber Collins.

Jeremy Hapgood and his brother told police that they tried to hold their uncle and keep him on the floor, but "Arthur was going crazy," so they ran out of the apartment. Someone then yelled that the baby, Zaniyah Calloway, was still in the apartment.

Arthur Hapgood's stepdaughter told police that she was holding Zaniyah when Hapgood began to act strangely and grabbed the knife. She said that her stepfather cornered her and the baby in the living room, and then moved a table to block a doorway so that she couldn't leave, according to the report.

"She reported that Arthur walked toward her and stabbed Zaniyah in the left side of her torso," the report says. The baby fell to the floor and the stepdaughter ran outside.

Jeremy Hapgood told police that he ran back in and saw the baby on the floor with a deep cut to her abdomen and lots of blood. Arthur Hapgood was lying next to the girl, and nearby was a bloody kitchen knife, according to the police report.

Jeremy Hapgood said he grabbed the baby, ran outside and remained there until police arrived. Police initially identified Arthur Hapgood as the baby's uncle, but said that after investigating further they were not sure if there was a blood relation.

Police said that Hapgood's mother, Roberta Hapgood, had been helping care for the baby, and might have been baby-sitting her on Monday. The baby and her mother stayed with Hapgood's mother on occasion, police said. Arthur Hapgood was caring for the baby when the incident occurred, police said.

After people in the apartment fled, according to the police report, Arthur Hapgood stripped naked and threw his bloody clothing outside. He was naked when Bristol officers arrived a moment later and confronted him in the apartment. Officers arrested him without incident.

In the meantime, police and paramedics worked to save Zaniyah. She was taken to Bristol Hospital, then flown to Connecticut Children's Medical Center in Hartford, where she died at 9:53 p.m.

Zaniyah, who was called Nyia by her family, and her mother, Shakyia Clay, were not living at the home where the stabbing occurred. Their address is listed in court records as a local shelter.