STANFORD — A Stanford University undergraduate student found dead in a campus fraternity in January died from an accidental fentanyl overdose, investigators said Wednesday.

Eitan Michael Weiner — who was the son of a prominent professor and administrator — officially died from “fentanyl toxicity,” colloquially known as an overdose, the Santa Clara County Sheriff’s Office confirmed.

Weiner was found unresponsive in Theta Delta Chi fraternity on Stanford’s Lomita Drive just after 10 a.m. Jan. 17. Firefighters pronounced him dead minutes later.

Later that same day, the Stanford Department of Public Safety issued a warning to students to avoid medications not prescribed to them — and imitation medications — after reports that illegally manufactured pills containing fentanyl have become more rampant in the U.S.

The narcotic is a synthetic opioid similar to morphine, but much stronger, and has been linked to the dramatic rise in death by opioids in recent years.

Within a few days, Weiner was identified by university officials as the son of associate professor of history Amir Weiner and associate vice president for medical center development Julia Erwin-Weiner.

In a letter to the Stanford community, vice provost for student affairs Susie Brubaker-Cole wrote that the university would remember Weiner for his kindness and intellectual depth.

“While I did not have the pleasure of knowing Eitan, I have been learning about him through his friends and family, who say he was full of love, joy, wit, curiosity and loyalty as a son, brother and friend,” Brubaker-Cole said in the letter. “Inspiring yet humble, he was incredibly well-read and deeply interested in history, politics and current events.”

Anyone with information on this case is asked to contact the Santa Clara County Sheriff’s Office at 408-808-4500. Alternatively, you can contact the Sheriff’s Office Investigative Services anonymous tip line at 408-808-4431.