BANGOR – Two men are being held at the Penobscot County Jail on probation violations as county officials probe the theft of thousands of gallons of heating fuel that was sold at a cut-rate price to customers who also could face charges.

As prices for fuel rose last fall and into this year, Benjamin Tibbetts III, 29, of Brewer and Michael Gonsalves, 41, of Kenduskeag allegedly sold stolen fuel at $1 per gallon, well below the average $1.85 per gallon that was paid during the five months the thefts occurred, a prosecutor said.

The fuel they sold may have kept those who bought it warm during the winter, but in some cases the customers may end up in hot water.

Tibbetts was the principal in the thefts of an estimated $17,000 in fuel while Gonsalves lined up prospective customers, Mike Roberts, Penobscot County deputy district attorney, said Monday.

As part of the investigation led by Detective John Trask of the Penobscot Sheriff’s Department, authorities learned that Tibbetts reportedly had been selling fuel on the side since October from Malenfant’s Fuel and Bottled Gas Co. in Milford, where he had worked until he was fired earlier this year.

On Feb. 22, after he was fired, Tibbetts allegedly stole a Malenfant’s fuel truck loaded with fuel oil and in rapid fashion sold it, Roberts said. The empty fuel truck was found at 3:45 a.m. the next day in Carmel.

“It wasn’t even a question of overnight – it was a question of several hours,” the prosecutor said.

Both men were on probation at the time of the incidents, and they were arrested separately earlier this month for violating their probation.

Tibbetts was on probation following a conviction for burglary, while Gonsalves was on probation after a conviction for unlawful possession of scheduled drugs.

A hearing to revoke Tibbetts’ probation is scheduled for April 25 in Penobscot County Superior Court; no formal date has been set for a hearing for Gonsalves, Roberts said.

The cases against the pair could go before the Penobscot County grand jury, and other charges could be filed against them, he said.

Authorities estimate that as many as 25 people purchased fuel from Tibbetts, and in some cases, more than once.

The investigation is focusing on who bought fuel, how much they bought and how often they bought it, the prosecutor said.

Roberts said that it is unlawful to possess stolen property if one knows it was stolen or reasonably should have known it was stolen.

“We believe there was a pretty wide range as to how much fuel these people received,” Roberts said.

In some cases, authorities still have to verify whether fuel was received at all, and in other cases, it may be a situation where people didn’t realize they were purchasing stolen fuel, he said.

Still, purchasing fuel at nearly half the going price should have sent up red flags, Roberts acknowledged.

“If someone is offering you fuel at $1 a gallon in Maine, you probably should be asking them some questions,” Roberts said.