Updated

A fraternity chapter at the University of Michigan has been suspended after semi-nude photos of men posing with U.S. flags as part of a party invitation circulated online.

Pi Kappa Alpha said Tuesday that it placed the Ann Arbor school's Beta Tau chapter on interim suspension. One picture included a group of men and a large flag, and accompanied an email sent to a sorority about the party. Other photos showed individual men with smaller flags.

Justin A. Buck, Pi Kappa Alpha's executive vice president, said the photos were "inappropriate and offensive" and he was disappointed by the chapter.

"Countless undergraduate and alumni members throughout our organization have contacted the office voicing their displeasure and the fraternity is taking this situation very seriously," Buck said in a statement. "Pi Kappa Alpha does not condone this behavior."

Beta Tau chapter President Ryan Lee told the Detroit Free Press that the image and email were supposed to be satirical and weren't meant to be circulated beyond one sorority. He said the fraternity meant no disrespect and aims to make amends.

"We did not mean to disrespect the sorority, veterans, America or the flag at all in the picture, and we apologize if anyone was offended," Lee said.

The Michigan Daily and AnnArbor.com report the Interfraternity Council, a self-governing body made up of fraternity members, is investigating. The school's Office of Greek Life also is investigating. Both are expected to determine whether further discipline is appropriate.

University officials learned of the photos Monday, said school spokesman Rick Fitzgerald.

"Most of the discipline with fraternities and sororities comes with Interfraternity Council or the national organization itself," Fitzgerald said. "Every situation is different."