SAUK RAPIDS, MINN. – Officials are seeking the public's help in investigating a series of suspicious grass fires sparked this week in Benton County.

Since Monday, the Benton County Sheriff's Office and other agencies have responded to seven grass fires in county ditches northeast of Sauk Rapids.

The frequency of the fires, along with evidence found at some of the scenes, has led investigators to believe some or all of the fires were intentionally set, according to Benton County Sheriff Troy Heck.

"The main thing is that there have been that many so close together," Heck said. "It's really unusual."

The fires were reported between 9 a.m. and 1 p.m. Monday-Thursday in Minden, Watab, Maywood and Mayhew Lake townships. Heck said all the fires were relatively small and were quickly contained.

Anyone with information is asked to contact the Sheriff's Office at 1-320-968-7201 or Tri-County Crime Stoppers at 1-800-255-1301.