A University of South Florida doctoral student, Hisham Abugharbieh, has been charged with murdering his roommate, Zamil Limon, and a second student, Nahida S. Bristy.

Limon’s remains were discovered in Tampa after both he and Bristy were reported missing in mid-April.

Authorities say Abugharbieh was already a person of interest and was arrested after a SWAT standoff at a residence.

He now faces two counts of first-degree murder along with additional charges related to concealing evidence and tampering, the USA Today has reported.

The search for Bristy continues as investigators say the case has deeply shaken the community.