Elizabeth, New Jersey: A self-proclaimed "home-free" hitchhiker who became an internet celebrity earlier this year for using a hatchet to stop a fight is suspected of beating a New Jersey lawyer to death, US authorities said on Thursday.
Caleb "Kai" McGillvary, 24, was last believed to be in Philadelphia, said Union County Prosecutor Theodore Romankow.
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Caleb 'Kai' McGillvary, who found fame after fending off an attacker with a hatchet, is now a suspect in a brutal murder case.
"We don't know where he is," Mr Romankow said. "But we do know this man is used to being on the road and he is considered dangerous."
Known as "Kai the Hatchet Wielding Hitchhiker", Mr McGillvary took a star turn after intervening in an attack on a California utility worker. He described using a hatchet he was carrying to repeatedly hit a man who had struck the worker with his car then accosted him.
"In the past he has had the ability to use the back end of a hatchet and it's very possible he may be carrying that," Mr Romankow said.
Joseph Galfy Junior, was found dead in his home on Monday, two days after authorities said he met Mr McGillvary in New York City. He was found wearing only his underwear and socks by police who went to his home to check on his wellbeing, the prosecutor said.
Statements posted on Mr McGillvary's Facebook page following the homicide indicated the encounter was sexual in nature, Mr Romankow said, though he declined to go into specific detail.
On his Facebook page, Mr McGillvary's last post, dated Tuesday, asks "what would you do?" if you awoke in a stranger's house and found you'd been drugged and sexually assaulted. One commenter suggests hitting him with a hatchet — and Mr McGillvary's final comment on the post says: "I like your idea."
Mr McGillvary gave a rambling, profanity-laced five-minute interview to a Fresno television station that went viral, with one version viewed more than 3.9 million times on YouTube. He later appeared on ABC's Jimmy Kimmel Live!
Mr Romankow said Mr McGillvary had cut his long hair since the interviews. Mr Kimmel asked him what people were saying to him since the February 1 incident in Fresno, California. "Hey, you're Kai, that dude with the hatchet," he responded.
Mr Romankow said Mr McGillvary traded on that celebrity to meet fans across the country.
Mr McGillvary met Joseph Galfy Junior, on Saturday in Times Square. Investigators know he was there based on witness accounts, the prosecutor said.
"He was well known," Mr Romankow said.
Mr McGillvary spent at least two nights in Galfy's brick home on a cul-de-sac in Clark, 32 kilometres west of New York, Mr Romankow said.
Prosecutors said Galfy drove Mr McGillvary to the train station on Sunday and Mr McGillvary boarded a train to Asbury Park to meet a fan before returning and being picked up by Galfy later in the day. Later that night, Mr McGillvary called the fan again asking her for a ride, Mr Romankow said. She couldn't pick him up, and Mr McGillvary's phone went dead after that.
According to a police reconstruction of his travels after leaving Clark, the suspect somehow got back to the train station on Monday and returned to Asbury Park to meet the fan. The two travelled to Philadelphia. After lunch, they travelled to Glassboro, in southern New Jersey, and he stayed with another fan there. On Tuesday he boarded a train to Philadelphia.
Mr McGillvary had mentioned at one point heading to Georgia to visit a girlfriend, police said.
Mr McGillvary swiftly gained notoriety after he was interviewed about how he stopped the attack on a utility worker. Mr McGillvary said he was travelling with a man, now facing charges including attempted murder, who veered into a Pacific Gas & Electric worker.
After the driver got out of the car, walked up to the utility worker and allegedly told him "I am Jesus and I am here to take you home". Mr McGillvary pulled a hatchet from his backpack and struck the driver in the head several times to subdue him, The Fresno Bee reported.
Last month, the driver entered a plea of not guilty by reason of insanity, the newspaper reported.
During his appearance on Jimmy Kimmel, Mr McGillvary said he prefers to be called "home-free" instead of homeless.
Mr McGillvary also goes by the names Kai Lawrence, Caleb Kai Lawrence and Kai Nicodemus, prosecutors said. A reward of $US5000 was offered for information leading to his arrest.