ELLIS, Kan. -

The Ellis County Sheriff's department is still investigating a number fires they believe were caused by arson that occurred in March and April.

Chris Miller of Ellis has been collecting donations to offer a reward for information that will help lead to an arrest. The reward is now up to $4,000. Miller says he lost $50,000 in property damage in one of the fires.

Police believe someone set at least 16 fires throughout rural Ellis County in a three week period. No one has been injured and no occupied homes have caught fire.

One fire burned about three miles of land. The area was full of cliffs and hills, making it difficult for fire crews.

"We've got ninety volunteers who work jobs, who have to get off there jobs to come do this," fire chief Dick Klaus said. "They are paid, but what they went through the other night they aren't paid enough.

The sheriff's department says they have a number of leads and people of interest, but they are still investigating. They also have extra crews patrolling rural Ellis County.

The sheriff's and fire departments are asking the community to try to stay out the way when there is a fire. They also ask the community to be alert and to call 785-625-1040 or 1-800-KS-CRIME if they notice anything unusual, even if it is online or on social media.

There are no suspects as of May 13. Police say they are still following up on leads, but there have been no more suspicious fires since early April.