FONTANA ( —An off-duty Fontana police officer is being credited with the arrest of three men who siphoned nearly 300 gallons of fuel from a San Bernardino County gas station.

Freddrick Hunter, 38, Edward Dawson, 32, and 42-year-old Terry Washington were caught in the act and arrested for grand theft on May 22, according to the Fontana Police Department.

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According to a news release provided by police, an off-duty officer noticed a suspicious van and a gold Toyota Camry at a Mobile Gas station located at 16925 Foothill Boulevard around 11:45 a.m. that day and called authorities.

“The officer noticed that the van appeared to be sucking gas from the underground fuel tanks,” as the occupants of the Camry provided a lookout, Sgt. Doug Imhof said.

When patrol officers arrived on scene, they found large containers filled with gas inside the van.

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“They made it look like the van was broken down in the parking lot and parked over one of the access holes for the tanks,” Imof said.

He described the “elaborate set-up” that allowed for such a massive haul as a “rare” occurrence.

“I have seen it before but not often,” he told CBS2’s Adrianna Weingold. “It’s kind of rare.”

Police believe the suspects also siphoned fuel from the same gas station the day before their arrest.

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They are investigating whether the suspects hit other gas stations in the area.