Caleb "Kai' Lawrence McGillvary

ELIZABETH, N.J. - A man who gained Internet fame as "Kai, the hatchet-wielding hitchhiker" says he's not guilty of a murder charge.

Caleb McGillivary is being held in a New Jersey jail after he waived extradition following his arrest in Philadelphia on May 16.

The 24-year-old is charged with beating 73-year-old lawyer Joseph Galfy to death after they met in New York City. Galfy's body was found in his Clark, N.J., home.

When a reporter asked if the killing was self-defense, McGillivary responded Thursday, "I don't know. You tell me." As McGillivary was being led to jail, he told reporters he wasn't guilty.

He also thanked supporters.

McGillivary gained a dose of fame in February when he was interviewed after he intervened with a hatchet in an apparently unprovoked attack on a Fresno, Calif., utility worker.