A Long Island teenager claims he was brutally beaten outside a Pennsylvania State University fraternity Sunday after revealing he was gay in the midst of a homophobe.

John Mateer, 19, declined to call police after the beating but posted photos of his injuries on Twitter. "Don't let a frat guy know that you're gay," he wrote. "I am bleeding on my phone."

Mateer is a student at Queens College in New York and was visiting friends at Penn State when the attack happened. The assault happened outside a fraternity house but when the suspect was arrested Monday, the State College Police Department confirmed he was not a member of the fraternity.

Since there was no initial police report, details of how the assault was triggered came exclusively from Mateer's Twitter updates.

"Got the living shit kicked out of me," Mateer wrote. "The brother admitted that he hated gays. Proceeded to kick the shit out of me."

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The teen received an outpouring of support on Twitter, and the attack was condemned by Penn State officials in a statement.

"Violence in any form is repulsive and hurtful, and those responsible should and will be held accountable for their actions," the statement read.

Authorities aren't investigating the assault as a hate crime because Pennsylvania law does not consider LGBTs a protected class.