A teenager who killed an Arkansas police officer days after a violent rampage at a gay bar left a "desperation note" around the time he attacked the bar and fled the state, Bristol County District Attorney Paul Walsh Jr. said Monday.

The note, which authorities did not immediately release, was found in a search of Robida's house Thursday, hours after he allegedly attacked three men in a gay bar, slicing some of his victims with a hatchet and shooting two of them. Robida died Sunday in a shootout with Arkansas police.

In addition to the message, police found items including an apparently homemade poster with a Nazi swastika and anti-Semitic writings, as well as a makeshift coffin, Walsh said.

"We didn't interpret it necessarily as a suicide note, but it was certainly the note of a desperate man who had some plans to continue doing something violent," Walsh said.

Police said Robida returned home after attacking the bar, and it was unclear whether he left the note before or after the attack.

On Saturday afternoon, Robida allegedly shot and killed a police officer who pulled him over in Gassville, Ark., then led police on a 20-mile chase. Prosecutors say he crashed his Pontiac Grand Am and fatally shot his passenger, 33-year-old Jennifer Rena Bailey, a mother of three from West Virginia with whom Robida used to live.

Police opened fire and shot Robida twice in the head, and he died the next day.

Autopsies of Robida, Bailey and Sell were expected to be completed Monday and the results would be given to investigators, J.R. Howard, director of the Arkansas State Crime Lab, said.

In West Virginia, police said they were trying to piece together whether Bailey went with Robida willingly. There were no signs of a struggle at Bailey's house, and Robida had lived in West Virginia with the mother of three for a short time, members of the West Virginia State Police said.

Three of Robida's friends from a home page the teen created on the Web site MySpace.com told The Associated Press that Bailey was Robida's ex-girlfriend. Police said they were checking e-mails and Internet correspondence between the two that they hoped would clarify their relationship.

Walsh said he has sent four investigators to assist authorities in Arkansas and two more to West Virginia to assist in the investigation.

Police are looking whether Robida had any accomplices in New Bedford or beyond, though evidence suggests he acted alone, Walsh said. They are also trying to determine where Robida got his handgun, a Ruger firearm. In Massachusetts, handgun owners must be at least 21 years old.

Walsh said he feared Robida's arrest could have been even bloodier, particularly if he had been confronted in a public place. New Bedford authorities had issued public warnings that they considered Robida armed, dangerous and possible suicidal.

"I really thought he was going to take five or six people with him," Walsh said. "My fear was that he'd shoot up the works."