Norwalk police say they arrested three New York men Tuesday after they allegedly tried to steal used cooking oil from a local restaurant.

The attempted theft happened at Dairy King on Main Street.

Owner John Ioannidis says when he arrived to open up the restaurant, he saw three men with a truck, a generator and a hose trying to suck oil out of the vat where the business's used cooked oil is kept.

"My eyes opened up and I was like, 'Oh my god, I'm actually catching them doing it,'" he says.

Ioannidis says he yelled at the men and they jumped into the truck and took off.

He says he was able to snap a picture of the license plate and with that picture, police were able to pull them over on I-95 in Stamford. Officers have identified the men as Frederico Ferreira, 31, of Yonkers; Juan Nunez, 31, also of Yonkers; and Jeiron Triunfel, 25, from the Bronx.

Ioannidis says thieves have been stealing used oil from them for more than a year now. He says other restaurants on Main Street and Westport Avenue have also been hit.

The used grease can be sold to recycling plants, where it can be used as biodiesel fuel.