A Wisconsin school district has put a staff member on leave after some high school students from found recording devices in their hotel rooms during a field trip to Minneapolis.

The response was a cautionary measure that is standard during a police investigation, Madison School District spokesman Timothy LeMonds told the Wisconsin State Journal for a story published Friday.

Minneapolis police spokesman John Elder declined Friday to confirm a report by the police chief in the Madison suburb of Cottage Grove that the recording devices were hidden cameras. Cottage Grove Police Chief Dan Layber also told the Madison newspaper that his department helped Minneapolis police execute a search warrant Thursday at a house in Cottage Grove. No arrests were made.

This March 31, 2011, photo shows the Minneapolis downtown Hyatt Regency in Minneapolis. A Wisconsin school district has put a staff member on leave after some students from Madison East High School found recording devices in their hotel rooms during a field trip to Minneapolis. The students stayed at the Hyatt Regency. (Tom WallaceStar Tribune via AP)

This March 31, 2011, photo shows the Minneapolis downtown Hyatt Regency in Minneapolis. A Wisconsin school district has put a staff member on leave after some students from Madison East High School found recording devices in their hotel rooms during a field trip to Minneapolis. The students stayed at the Hyatt Regency. (Tom WallaceStar Tribune via AP)

The Madison East High School students stayed at the Hyatt Regency in downtown Minneapolis last weekend. LeMonds declined to specify the student group to protect the identities of the students involved.

Elder declined to say how many devices were found, except that it was more than one. He said investigators were still trying to determine how the devices got into the rooms, and that some of the possibilities being examined had nothing to do with the hotel or its staff.

“At this time we are analyzing these devices to determine their capabilities and see if there is any data to be mined from them,” Elder told The Associated Press.

No suspects were in custody, he said.

Interim Principal Brendan Kearney said in a letter to families Thursday evening that his staff was working hard to support the affected students and families.

“I want you to know that we will continue to do everything we can to protect our students and to see that anyone responsible for harming them is held accountable,” Kearney said.