MADISON, Wis. -- Members of Sigma Phi Epsilon's Madison chapter are being investigated in connection with a fraternity stunt last week in front of their house on Langdon Street.

University of Wisconsin-Madison leaders said the investigating surrounds what some are calling a hazing.

But the fraternity argued that what happened was purely a stunt and not hazing.

The incident took place last week Friday, outside the Sigma Phi Epsilon fraternity house. A student who belongs to another fraternity told UW-Madison student paper The Badger Herald that he saw members pouring buckets of vomit, urine and feces on three other fellow fraternity members. He said he could smell the stench from across the street.

UW-Madison Associate Dean of Students Kevin Helmkamp said he can't comment on specifics of the investigation but said the university has a good idea of what happened. He said university officials are still trying to determine if what took place was indeed a hazing or just an act of stupidity.

"It hasn't been ruled out," Helmkamp said. "Certainly, it has played out differently than initially reported to us. We're still having conversations because of the nature of it, to determine what's the best response."

UW-Madison Sigma Phi Epsilon President Mike Miesen provided this statement to WISC-TV, from the UW-Madison Sigma Phi Epsilon Alumni Board:

"The actions that took place outside of the Sigma Phi Epsilon fraternity house on Saturday, May 3 were inappropriate and do not represent the values and beliefs that Sigma Phi Epsilon represents, nor the values of the Greek system at UW-Madison. The alumni board has been assured that the actions of May 3 did not involve hazing. No members were required to participate and only did so voluntarily," the alumni board said in the statement.

The university said it's considering punishments against the individuals who took part, in addition to the fraternity as a whole. Punishments could range from warnings to probation or possible suspensions.

A decision on what action to take will come by the end of this week, WISC-TV reported.