A "corroded" but live grenade was found Friday in the basement of the Sayville Modern Diner by a contractor fixing a gas leak, the restaurateur said.

Suffolk County police said it's not clear how old the grenade is and how long it's been there. Diner owner Dimitrios Sioutopoulos said the grenade was found in a crawl space that had rarely been touched since his great uncle opened the business in 1933.

Friday night, Sioutopoulos said he was too unnerved over the double trouble to open for business, even though authorities said the gas leak repairs had passed inspection.

"I've been very lucky, thank God," Sioutopoulos said from the diner. "I'm a little shaken up."

Emergency services police disposed of the grenade after getting the call about 3:25 p.m. The case has been referred to the arson squad.

Workers from a plumbing and heating company had been there fixing a gas leak since Thursday, when Sioutopoulos arrived at 6 a.m. to open for breakfast and smelled the "awful" gas fumes.

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When they went into a crawl space Friday to repair a gas line, the diner owner said, they came across the grenade.

"In the crawl space was . . . what appeared to look like a hand grenade," Sioutopoulos said. "The diner's been here forever and nobody ever actually had to get into certain areas of the building that needed repairs, so you didn't know."

"It was an actual hand grenade . . . It could have been World War II, it could have been anything. It was corroded. It could have been potentially dangerous," he said.

The diner owner said he was a "pretty big dude" who did not fit into the crawl space, but the "little guy" from Alan S. Gross Plumbing and Heating in Sayville snapped a photo, which was then shown to police.

"I'm just thankful that nothing happened to anybody," the restaurateur said.

Alan Gross, the plumbing company owner, said his two workers also were shaken up. The grenade was found next to a box of coupons from 1946, many of them for coffee, said Gross, who collects memorabilia.

"These last two days have been nothing but very interesting for me," Sioutopoulos said Friday night. "I'm probably going to open up for breakfast tomorrow morning."