A high school friend accused of killing a University of Pennsylvania student and dumping his body at a California park previously made “violent” comments online and defended the Confederate flag, a report said.

Samuel Lincoln Woodward, 20, who was the last person to see Blaze Bernstein, 19, alive, was arrested on Friday on suspicion of murder, Orange County Undersheriff Don Barnes said. Woodward appeared nervous while he was questioned about Bernstein’s disappearance and had scratched hands and dirt under his fingernails. He also avoided placing his hands on doors while leaving the sheriff’s office building.

Before he was taken into custody, Woodward posted disturbing comments that even prompted an anonymous user to say the Newport Beach man “scared” the individual. On one site, he defended the Confederate flag and said it illustrated Southern pride and wasn’t a symbol of hate, CBS Los Angeles reported.

When asked what he would have when stranded on an island, Woodward responded: “The Bible and a Colt. 45.”

Woodward reportedly said he wanted to learn “waterboarding” as a new skill. On the topic of human cloning, the Newport Beach resident wrote, “Just one of me in the world is already bad enough,” according to CBS Los Angeles.

“You are violence. It scares me,” one user wrote, to which Woodward replied, “I wouldn’t fight anybody unless they attacked me.”

Woodward listed his occupation as “Nerf games,” according to the jail’s website.

Bernstein’s body was found on Tuesday in a shallow grave at Borrego Park, where he and Woodward went nearly a week before he was reported missing. The Ivy League sophomore was home in California during his winter break.

Woodward told investigators he left the park after Bernstein didn’t return or respond to social media messages he sent him. Police were able to identify Woodward by using Bernstein’s Snapchat account. Woodward explained his dirty fingernails as a result of participating in a “fight club” where he fell in a “dirt puddle,” the Los Angeles Times reported.

Investigators ultimately linked DNA evidence between Woodward and Bernstein’s death. A motive in the alleged murder is still being determined.

Bernstein’s mother tweeted Friday after Woodward’s arrest that “revenge is empty.”

“It will never bring back my son. My only hopes are that he will never have the opportunity to hurt anyone else again and that something meaningful can come from the senseless act of Blaze’s murder. Now Do Good for Blaze Bernstein,” she tweeted.

The Associated Press contributed to this report.