Wichita ? Wichita State University is investigating its chapter of the Phi Delta Theta fraternity to determine if pictures posted on the Internet show hazing activities there.

“There were inappropriate activities that are under review,” Ron Kopita, vice president of student affairs, said Tuesday. “By definition, hazing has to be associated with treatment of pledges. You have to determine if it was actual hazing or fooling around.”

The fraternity’s national headquarters says the activities pictured were horseplay, not hazing.

Wichita State began the investigation Jan. 31 after an anonymous complaint, said Eugena Lee, director of the university’s Center for Student Leadership, which oversees fraternities. Lee said students were never endangered. She said the investigation should be done Monday.

Chris Purdum, president of the university’s Intrafraternity Council, said his organization was also investigating.

Kopita would not say what the pictures showed and said he did not know where they were posted. Pictures broadcast by Wichita television station KAKE included one image of a man bound with duct tape to what the station said was believed to be the staircase bannister at the fraternity house.

Another picture showed a bound man apparently being force fed, and two pictures showed other young men surrounding the bound man.

The fraternity’s national headquarters said in a news release that the allegations of hazing were untrue but added that it was assisting the university in its investigation. A confirmed case of hazing could result in the fraternity losing privileges, including the ability to recruit on campus.