SPOKANE, Wash. — Investigators arrested a man in connection with several fires at Beacon Cleaners on the Spokane South Hill thanks to a fingerprint left behind on a burned document.

The co-owner of Beacon Cleaners, Rodney Johnson, said they are still trying to figure out why someone would set two fires at their business within the span of a month.

“Very nerve wracking put it that way. Me and my business partner Mr. Kim were wondering, why would anybody do this to us,” said Johnson.

After shutting down for 12 days because of the fire, Beacon Cleaners set up a trailer to keep business going in the meantime.

“Kind of took us by surprise on the second one, we can't understand why the gentleman would want to burn us down in the first place, we're just cleaning people's clothes,” Johnson said.

Court documents estimate the fire caused more than $40,000 in damages.

It can be tough to find any evidence left behind in burned debris but investigators were successful.

“You'll see our investigators sometimes even down right next to the ground sifting through material to try to find evidence that may hold a connection. We have a lot more technology now than we ever did,” Spokane Fire Chief Brian Schaeffer said.

A partially burned Washington State Voter Registration card was discovered in the debris. Investigators sent it to the forensic lab to check for fingerprints and they were able to pull prints off it and get a match with fingerprints from Scott Lenway.

The voter card was not the only thing investigators found at the scene of the crime. They also found empty condiment packets.

The first time Beacon Cleaners was set fire in August, investigators found two empty mayonnaise packs on the ground. At the second fire in early September, investigators found empty hot sauce packets.

Investigators believe those empty packets also tie Lenway to the fires.

Spokane Fire says nine fires were set in the same area since August and it is likely Lenway will be facing more charges.

Lenway was supposed to appear in court Tuesday but investigators are still working on his charges.