(AP) --

Three men face murder charges and a fourth is being sought after a Clemson University student was shot and killed by masked intruders busting into his off-campus home.

The Pickens County Sheriff's Office said Monday the armed invasion of the home in a gated community aimed to rob the dead man's roommate of what they thought would be a big stash of marijuana. Electrical engineering student Steven Grich was killed.

Officers have warrants for the arrest of 18-year-old Lester Mosley of Central.

Arrested and charged with murder are 19-year-old Jordan Dalton of Central, 24-year-old Jaron Dalton of Six Mile, and 19-year-old Bernard Ramsey of Central.

Only a few grams of pot were taken during the robbery. Deputies charged Grich's roommate with simple possession of marijuana.

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