After the body of University of Pennsylvania student Blaze Bernstein was found earlier in January, much remains unknown about his alleged murder. The pre-med student was missing for more than a week before authorities discovered his body in a shallow grave in a California park.

Since then, a suspect has been arrested and charged with felony murder. Here is everything we know about the case so far.

Missing Persons Investigation

Bernstein, 19, was first reported missing by his family Jan. 3. He was last seen the day before, when he left his parent’s home to meet a friend. Bernstein was home on break from college when he disappeared.

Body Found

Authorities discovered Bernstein’s body in a shallow grave in Borrego Park more than a week after he went missing. Police immediately announced they were investigating the death as a homicide and said they believed he was killed the same night he disappeared.

Police Interview Friend

Police interviewed the last person to see Bernstein alive, who was apparently a friend from high school. The unidentified friend said he picked up Bernstein, who told them they would be meeting up with another friend, and drove him to Borrego Park a little before midnight, according to documents obtained by the Orange County Register.

The friend said Bernstein entered the park by himself and did not return or answer messages when he attempted to contact him. The friend said he left the park but returned again later when Bernstein still had not responded.

Authorities said the friend had scratches on his hands and dirt under his fingernails when they spoke to him two days after Bernstein’s disappearance. The friend said the injuries were from a “fight club” he was a part of. Authorities said the friend was “visibly shaking” and appeared nervous and was actively trying not to touch anything around him. Still, police did not immediately identify the friend as a suspect in the case.

Suspect Arrested

Samuel Woodward was arrested a few days after Bernstein’s body was discovered. Woodward, 20, was identified as having gone to the same high school as Bernstein and was also identified as the last person to see him alive.

Authorities said “inconsistencies” in Woodward’s story led them to focus on him as a suspect, according to the Daily Pennsylvanian. DNA evidence also tied Woodward to Bernstein. Woodward was subsequently charged with felony murder, according to a complaint filed in Orange County Superior Court.

Prosecutors alleged Woodward killed Bernstein with a knife, stabbing him repeatedly before burying him in the park.

Cause Of Death

Police had not yet revealed Bernstein’s official cause of death but said an autopsy was underway. An unidentified source, however, told the Orange County Register Bernstein was stabbed at least 20 times.

Motive

Following Woodward’s arrest, Bernstein’s parents said they believed their son’s death may have been a hate crime. Woodward reportedly told police Bernstein tried to kiss him when they went to the park that night and that he pushed him away.

“Our son was a beautiful gentle soul who we loved more than anything,” Bernstein’s parents said in a statement. “We were proud of everything he did and who he was. He had nothing to hide. We are in solidarity with our son and the LGBTQ community. If it is determined that this was a hate crime, we will cry not only for our son, but for the LGBTQ people everywhere that live in fear or who have been victims of hate crime.”

Police had not yet said what they believed the motive was.