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COLLEGE STATION (CBSDFW.COM/AP) — Police said a preliminary investigation has determined that a Texas A&M University student found unresponsive at a fraternity house died of a drug overdose.

College Station police said in a statement that the unidentified 19-year-old was found early Saturday at the Sigma Nu fraternity. The student, who was a member of the fraternity, was pronounced dead at College Station Med hospital.

Investigators say it’s not clear what drug the student ingested.

Police determined other drugs were in the house and four young men, ages 18 to 21, were arrested for possession. Others were cited for having drug paraphernalia.

Two of the men, 21-year-old Samuel Patterson and 20-year-old Michael Frymire, were charged with possession of a controlled substance.

Patterson was charged with having fewer than 20 units of LSD and less than one gram of MDMA, and Frymire for having less than one gram of hash oil.

The two other men, 18-year-old Christian Sandford and 21-year-old Ty Robertson, were charged with possession of marijuana.

Frymire is from Dallas and Robertson from Granbury.

The fraternity’s national office issued a statement saying Sigma Nu will assist authorities with the investigation.

“Our hearts are filled with sorrow as we grieve the loss of this young man,” said Sigma Nu Executive Director Brad Beacham. “Our thoughts, prayers and deepest condolences are with his family and loved ones. We appreciate the immediate support and care the Texas A&M community is providing during this very difficult time. We will be working with Texas A&M officials to provide as much continuing support as possible to those affected. The Fraternity will assist, however possible, with the investigation by local authorities. At the appropriate time, the Fraternity and University will complete their own investigations.”

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