A former classmate of University of Pennsylvania student Blaze Bernstein, whose body was found Tuesday in a California park, was reportedly nervous when he was interviewed by detectives, who have launched a homicide investigation into the 19-year-old’s death.

Investigators with the Orange County Sheriff’s Department interviewed a supposed friend of Bernstein’s who was seemingly anxious as they spoke to him, The Mercury News reported, citing an affidavit.

The friend, a former classmate at Orange County School of the Arts in Santa Ana, was “breathing heavy, talking fast and visibly shaking” as he spoke to investigators about his encounter with Bernstein on the night he went missing.

The friend told law enforcement that he and Bernstein spoke via Snapchat on Jan. 2 – the night he went missing. He reportedly picked Bernstein up to “hang out” and “catch up” in a Hobby Lobby parking lot before driving to meet another friend from high school shortly before midnight at Borrego Park.

The friend said Bernstein left his car and walked into the park alone, while he waited in his car for about an hour and attempted to contact Bernstein on Snapchat.

Around 1 a.m., the friend claimed he left the park and drove to his girlfriend’s house roughly 30 minutes away, before returning to the park around 3:40 a.m. The friend said Bernstein never responded to him on Snapchat.

On Jan. 4, according to The Mercury News, investigators spoke to the friend at Borrego Park and noticed small scratches on his hands with “dirt under the fingernails.” The friend reportedly said he “fell into a dirt puddle” when he was sparring as part of a “fight club” he was in.

IVY LEAGUE MURDER? UPENN STUDENT FOUND DEAD IN CALIFORNIA PARK; HOMICIDE INVESTIGATION LAUNCHED

The friend allowed two detectives to search his car, where they reportedly found “hiking and camping equipment in the rear of the vehicle, a large empty plastic bin on the backseat, and a black belt on the passenger seat floorboard.”

While detectives said the friend’s story “stayed fairly consistent” as they continued to interview him at sheriff’s headquarters in Santa Ana, he allegedly couldn’t remember his girlfriend’s last name or where she lived. Detectives also said the friend avoided touching doors at the sheriff's offices following an interview.

"On their way out of sheriff's headquarters, (investigators) noticed every door (the friend) had to touch on the way out of the building he pulled his jacket over his hand to prevent his hand and fingers from touching any part of the doors he touched," the newspaper quoted the affidavit as saying.

Carrie Braun, a spokesperson for the sheriff's department, said at a press conference Wednesday that while no arrests have been made, deputies are "still following up on multiple leads."

Bernstein’s body was found in the brush surrounding Borrego Park after days of searching by rescue teams, with assistance from drone pilots, the Orange County Sheriff’s Department announced Wednesday. An autopsy was expected to take place later that day.

Bernstein was a pre-med student at the Ivy League University, who was back home in Lake Forest on winter break and reportedly expected to return to campus on Sunday.

More than 300 people attended a candlelight vigil for Bernstein at the park Wednesday night.