(CBS/AP) PHOENIX - Dale Hausner, a serial killer convicted of murdering six people in a shooting spree that terrorized Phoenix in 2005 and 2006, was found dead Wednesday in his death row prison cell, officials said.
The 40-year-old Hausner was found unresponsive around noon Wednesday in his one-person cell at the Eyman state prison complex in Florence, the Department of Corrections said. He was pronounced dead at a hospital about an hour later.
Hausner's death was under investigation and the cause was unknown.
Hausner, a former airport janitor, was given six death sentences and hundreds of years in prison for killing six people and attacking 19 others in a series of random shootings in the Phoenix area. He denied any involvement in the attacks and suggested his former roommate might have carried out some of the crimes.
Authorities say Hausner preyed on pedestrians, bicyclists and animals in attacks that ended in August 2006 when he and roommate Sam Dieteman were arrested at the apartment they shared in Mesa. Inside, police found guns, news clippings of the killings and a city map marked with the locations of some of the shootings.
Dieteman, who pleaded guilty in two of the killings and was sentenced to life in prison, testified against Hausner, saying they cruised around late at night looking for strangers to shoot.
The "serial shooter" attacks and an unrelated serial killer case kept neighborhood watch groups on high alert in the summer of 2006. Families stayed inside and authorities called meetings that drew hundreds of people who learned more about the attacks and were encouraged to provide tips.
Police said their big break came when one of Dieteman's drinking buddies, Ron Horton, called police to say Dieteman had bragged about shooting people.
"They called it `RV'ing.' Random Recreational Violence," Horton told The Associated Press in a 2006 interview. Horton died in 2008.
As a murder defendant, Hausner took several unusual steps. Shortly after his arrest, he held a jailhouse news conference that ended when his newly appointed public defender entered the room and whispered that he should stop talking to reporters.
Even though Hausner had denied any involvement in the attacks, he took an odd turn during the penalty phase of his trial when he apologized to the families of every victim.
"I'm not up here to point the finger at anybody else and say, `Have mercy on my poor and withered soul,"' Hausner told jurors. "I'm willing to accept my punishment like a man without blaming anybody."
In talking to jurors about how the names of infamous serial killers arose during a police interview, Hausner said he was fascinated with serial killers Charles Starkweather and Jeffrey Dahmer, saying he wondered how Dahmer could eat the remains of some of his victims and then go to work the next day. In a statement to jurors just before deliberations began in his trial's penalty phase, Hausner said the Hausner name would likely become as infamous as Charles Manson's.
Since his convictions, Hausner had asked that he be executed quickly.
County authorities have said that while he was awaiting trial, Hausner tried to kill himself with an overdose of cold tablets.
At his trial, Hausner cast himself as a busy divorced father of a sick daughter, a ladies' man and a go-getter with side jobs in standup comedy, bartending and boxing photography. He also made an appearance in a TV commercial for a personal injury law firm.
He offered alibis that included being at his girlfriends' houses, shopping at the grocery store, driving in another part of the Phoenix area or taking care of his daughter.