A former classmate of murdered Blaze Bernstein has been arrested on suspicion of his homicide.

The 19-year-old University of Pennsylvania student was reported missing by his family after he failed to show up for a dental appointment. He had been on a winter break, visiting his parents in Lake Forest. Three days after his body was discovered in in a shallow grave in an Orange County park, police announced they’d arrested Samuel Lincoln Woodward, a former high school classmate of the victim, on suspicion of homicide.

On a Facebook group dedicated to finding Bernstein, his mother, Jeanne Pepper, called her son’s death “tragic and senseless”, while also posting a poll asking group members to vote on different ways to honor Bernstein’s legacy.

After news of the arrest, she told The Los Angeles Times, “I would just say that we are grateful for the fine men and women in the [Sheriff’s Department] who have worked tirelessly to get answers for our family, our community and the world.

“Nothing will bring back my son, so we ask the world to please honour Blaze’s memory by doing an act of kindness today. Don’t wait, do it now. Celebrate the goodness that still exists in this world in spite of these acts of senseless evil. People are good and Blaze knew that,” she said. “Honor yourselves and him.”

In an earlier interview, she spoke of how her 14-year-old daughter, Beaue, was heartbroken over her brother’s death, saying: “They were very close this past year, he really started to enjoy her and her antics. She looked up to him.”