WOODLAND, Maine — Reward money has been increased to $60,000 for information leading to the killer of a northern Maine sawmill owner who was shot to death during an apparent robbery four years ago.

Darrel Smith, 56, was killed Feb. 4, 2008, inside his sawmill adjacent to his home in Woodland, a town of 1,400 people next to Caribou. Police say Smith’s wallet and a safe were taken.

Smith’s family first offered a $30,000 reward for information leading to the conviction of the killer. The reward was later boosted to $40,000.

State police Detective Sgt. John Cote told the Bangor Daily News that donations keep coming in to the reward fund, allowing the reward money to be raised to $60,000.

Police say it’s a record reward for any state police case.

“We have new and updated information that comes into this case almost weekly,” Cote said, according to the Daily News. “And we have a detective who reviews it. I think that all that it will take is just that one little piece of information to lead us to the killer or killers. This is an active case.”

Smith owned and operated Smith’s Sawmill and Logging in Aroostook County.

Since Smith had no signs advertising the establishment and word of mouth was used to secure business, police believe that his killer or killers had to be familiar with the sawmill, according to the Daily News story.

It looks like a private residence. Police believe the perpetrator or perpetrators also knew he was running a cash-only business and would have money on hand since he did not accept credit or debit cards at his facility.