The roommate of one of the two University of South Florida graduate students who mysteriously disappeared this week has been charged with their murders. Hisham Saleh Abugharbeih — who was arrested after cops found 27-year-old Zamil Limon’s body Friday — is now facing two counts of first-degree premeditated murder with a weapon, the Hillsborough County Sheriff’s Office announced. Abugharbeih had originally been facing failure to report a death and unlawfully moving a body, as well as battery and false imprisonment. Hisham Saleh Abugharbeih has been charged with premeditated murder in the missing person case of his roommate and his girlfriend. Hillsborough County Sheriffâs Office The details of what officials called a “disturbing” case were still unclear, but police said they had gathered enough evidence to prove Abugharbeih had killed Limon and his girlfriend, Nahida Bristy, 27, who is assumed dead.…