The fraternity named in a discredited Rolling Stone feature about an alleged gang rape on a US college campus said Monday it will take legal action against the iconic pop culture magazine.

The University of Virginia chapter of Phi Kappa Psi said a Columbia University investigation into the story, released over the weekend, had demonstrated "the reckless nature" in which it had been reported.

In a statement, Phi Kappa Psi said it planned "to pursue all available legal action against the magazine" over the story, which appeared in November.

"Clearly our fraternity and its members have been defamed," said Stephen Scipione, president of the fraternity's Virginia Alpha Chapter.

"But more importantly we fear this entire episode may prompt some (sexual assault) victims to remain in the shadows, fearful to confront their attackers."

Rolling Stone retracted the story on Sunday and issued an apology on the heels of the Columbia University inquiry, which it commissioned after doubts emerged over the credibility of its source.

Published by the Columbia Journalism Review, the 12,000-word investigation found lapses in journalism standards at Rolling Stone from start to finish of the purported expose.

The author of the article, Sabrina Rubin Erdely, acknowledged Sunday she "did not go far enough" to verify the story, which hinged on the claims of a freshman student identified only as "Jackie."

The Columbia University inquiry faulted Rolling Stone for failing to verify the alleged victim's claims, or to give Phi Kappa Psi an opportunity to review the allegations in detail. afp