UCLA is investigating allegations that white fraternity and sorority members spoofed Kanye West and Kim Kardashian with clothing, padded rear ends and “charcoal”-covered foreheads as part of a “Kanye Western” party this week.

The school said in a statement that the Greek organizations involved, Sigma Phi Epsilon fraternity and Alpha Phi sorority, “have been placed on immediate interim suspension of all social activities pending the outcome of an investigation.”

The move came after a small group of African-American students confronted people outside the Sigma Phi Epsilon party, took photos and then asked UCLA officials to respond, according to the Daily Bruin.

A report in African-American student publication Nommo says students who took photos were surrounded by partygoers and urged to stop. ““It was the most surreal experience, the utter disrespect that we saw,” witness Lynzie Glover is quoted as saying.

The university responded with a statement:

While we do not yet have all the facts, the alleged behavior is inconsistent with good judgment as well as our principles of community. We remind students that while they are free to celebrate in ways that draw on popular culture, their specific choices can cause harm and pain to fellow members of their community. Put simply: Just because you can do something, does not mean you should.

Sigma Phi Epsilon's national leadership said in a statement that it's asking the UCLA chapter to “temporarily suspend activities” while UCLA investigates.

“Sigma Phi Epsilon is investigating claims that its UCLA chapter hosted an inappropriately themed social event with Alpha Phi sorority,” it stated. “The fraternity is aware of images of female guests dressed in offensive and racially insensitive outfits.”

The Westwood chapter has apologized, saying in a statement that it is “deeply sorry” for how some of its guests dressed for the Tuesday night event.

“A Kanye Western–themed party was intended to celebrate pop culture,” the chapter stated. “We realize that the theme showed a lack of judgment on our part and that some of the guests’ costumes were offensive to members of the Bruin community. We want our campus community to know that they can expect better from this fraternity.”