A truck driver whose towed wood chipper detached and slammed into a minivan, killing a father and his two small children, admitted to police that he did not properly check the vehicle before the crash and was speeding.

Bradley Demitras, 34, of Pine, who also told police he took stolen prescription painkillers and drank beer on the day of the crash, faces three counts of homicide by vehicle and involuntary manslaughter and a host of other charges in the April 13 crash on Route 8 in Richland.

A warrant for Mr. Demitras' arrest was issued yesterday.

The crash killed Spencer Morrison, 37, of Cranberry, and two of his 4-year-old triplets, Alaina and Garret. The third, Ethan, remained hospitalized in critical condition yesterday.

An affidavit in the case says investigators believe the trailer carrying the wood chipper was not properly latched and chained to the dump truck, and estimated the truck's speed at the time of the crash at 67 to 73 mph in a 45-mph zone.

It says that at the crash scene, Mr. Demitras "admitted that he failed to check the trailer connection, the locking pin and the safety chains prior to operating the vehicle on the roadway."

He also acknowledged not checking the connection when he gave a statement to police five days later.

In that statement, he told police, "I'm not going to lie to you, I was speeding," according to the affidavit. He estimated his speed at 50 to 55 mph but said he had not looked at the speedometer.

Mr. Demitras was driving the truck for his friend, James O'Connor, owner of O'Connor Enterprises, a tree-trimming business.

Mr. Demitras "admitted ... that he was hung over on the day of the incident after consuming an illegally possessed OxyContin tablet and half of a 750 ml bottle of bourbon whiskey on the previous night. Demitras also admitted that he had stolen six prescription Percocet tablets from James O'Connor's father earlier in the week and that he had taken one of those tablets at 8 a.m. and another at around [noon] ... he also consumed 12 ounces of beer at about 11:30 a.m.," the affidavit says.

The crash occurred at about 5 p.m. as Mr. Demitras drove north in the passing lane on Route 8. The 5,000-pound wood chipper broke free, crossed the center line and struck Mr. Morrison's Honda minivan, which was traveling south.

In addition to homicide and manslaughter, Mr. Demitras is charged with aggravated assault; reckless driving; driving at an unsafe speed; violating safety requirements for towed vehicles; having altered, forged or counterfeit documents; and operating without an inspection certificate.

Police said the dump truck's inspection sticker had been removed from another truck owned by O'Connor Enterprises. The dump truck had failed a safety inspection on Jan. 7 and had "a number of safety violations" that would have required it to be placed out of service, according to the affidavit.

Mike Manko, spokesman for Allegheny County District Attorney Stephen A. Zappala Jr., said he could not comment on the arrest warrant. He said Mr. Zappala and others would speak about the matter this morning.

Steven Townsend, attorney for the tree service, said Mr. O'Connor had no knowledge of any drinking by Mr. Demitras before the accident. He said Mr. O'Connor was aware that Mr. Demitras had a knee injury but did not know if the two had discussed what medications Mr. Demitras might have been taking.

He said Mr. Demitras was on a leave of absence from the company.

Mr. Demitras' attorney, Michael Moser, could not be reached yesterday.

In an interview last week, he said Mr. Demitras was distraught over the accident but had not driven in such a way as to cause the trailer to separate.

"It's his assertion he was not driving at all in a careless or reckless manner," Mr. Moser said. "I don't believe that the way he was driving was the cause of the separation of the chipper."