Riverside police say an arrest this week derailed a sophisticated scheme of stealing gasoline by overriding the pump counter and filling 5-gallon jugs.

The investigation began Jan. 20 when a Riverside officer pulled into a 7-Eleven at 26th Street and Harlem Avenue, then saw a man hurriedly leave the store with a gasoline nozzle still in his vehicle, tearing off the hose as he drove away.

The officer reviewed video surveillance, at first to get a license plate number but discovering what appeared to be an involved ruse to steal fuel, according to a news release from the Riverside police.

The video showed one person pulling up to a pump and removing its housing, then disabling the electronic device that measures the amount of gasoline delivered and tally of dollars owed.

That person then drove off, and a second person pulled up to the overridden pump and began to fill the SUV's tank and 11 5-gallon professional grade water fountain bottles in the back, police said. The second person appeared to panic and fled when the officer drove into the lot, tearing off the pump's hose.

Suspecting a sophisticated scheme, Riverside police didn't immediately chase after the SUV but were able to track the license plate and discover that the registered owner was already due in court on a previous charge of retail theft of motor vehicle fuel.

On Friday, Riverside police attended Bridgeview Court and arrested Darius Williams, 35, of the 400 block of Irvine in Hillside, and according to officials he gave a full confession detailing the scheme.

The second suspect, a man known to Williams only as "Mike the gas man," was the brains behind disabling the pump counters, Williams said, and also took part in selling stolen gasoline from the water bottles at $10 for 5 gallons.

Police searched the SUV owned by Williams and found 10 5-gallon water bottles, a hose and pump used for siphoning gasoline, and other materials used for transporting fuel, police said.

For the Riverside incident, Williams -- who told police he also stayed on the 11700 block of South State Street in Chicago -- was charged with retail theft of motor vehicle fuel and criminal damage to property, police said, both misdemeanors because he had fled the scene after only taking about $73 worth of gas.

"The defendant in this case gave a full statement that he and another individual known as 'Mike the gas man' conceived this plan to steal gasoline and then sell it on the West Side of Chicago," Riverside Police Chief Thomas Weitzel said in the release.

"This is an example of excellent work done by the original responding officer as well as the follow-up investigation by detectives," Weitzel said. "They looked beyond the simple theft complaint and were able to build a case."

"Mike the gas man" remained at large Saturday night, police said.

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