In his 25 years in business, John Papas said he only closed the doors to his eponymous cafe once for an extended period — three years ago when he undertook a major renovation. That was until the early hours on Sunday when a fire broke out in the relatively new kitchen at John Papas Cafe. Sunday morning breakfast-goers were greeted with the smell of smoke rather than the smell of bacon when they showed up at the East Hampton eatery at 18 Park Place. They found the glass front door shattered into tiny pieces where first responders broke through after being called at about 2:15 a.m. An East Hampton Village police officer on patrol spotted smoke. Volunteer firefighters with the East Hampton Fire Department found heavy smoke in the building and a fire in the kitchen, according to Gerry Turza, the first assistant chief.As customers peered through the windows at the Greek diner, a few hours after the last fire trucks had gone, the reason for the closure was not readily apparent (a sign did not go up until midday). The damage was contained to the kitchen. “I was very lucky that the policeman was outside and smelled something and I’m so grateful to those firefighters,” Mr. Papas said on Tuesday. Police quickly summoned him. “When I arrived here, there were four or five trucks and firefighters — about 30 of them, 40, I don’t know. It was like an army here. Customers, local people — it was like I had a big family here supporting me because I don’t really have many in this country. I am so grateful. They did a great job.” An Ansul system, a fire suppressant system designed for restaurants, had already been automatically activated to fight back the flames. Firefighters finished the job. The fire destroyed about a quarter of the kitchen, according to Mr. Papas, who leases the space, which is owned by Pat Trunzo.About a quarter of the kitchen was destroyed, Mr. Papas said. “It could be worse. . . . The dining room, it’s okay except for the smell of smoke.”The East Hampton Village fire marshal’s office is investigating the cause. Mr. Papas said he was told it may be electrical in nature, but it has not been confirmed. The question on everyone’s mind is this: When will John Papas Cafe reopen? “It’s too soon to tell,” the owner said. A lot has to be sorted out by the insurance companies. “If I take a wild guess? Two or three weeks.” Mr. Papas said the fire devastates him, but it is not the loss of business that is most upsetting. “I’m worried mostly about the people, the customers,” he said. “That’s why, the last three years, I haven’t had a day off!”This most certainly is not the vacation he had in mind.