The police said that six men, who appeared to be in their 40s, were in the coffee shop in the lobby of theHilton Garden Inn on 134th Street, near Kennedy International Airport, at lunchtime when one of the men shot another in the head before doing the same to himself.

The police identified the first man shot as Brian Weiss, 31, of Davie, Fla., and the shooter as Gary Zalevsky, 47, of Sunny Isles Beach, Fla. Efforts to contact their families for comment were unsuccessful.

It was unclear what prompted the gunfire. The four other men were being questioned by the police.

Hours after the shooting, guests and workers at the hotel were still unsettled, and streets remained cordoned off into the evening.

Shortly after 7:45 p.m., the medical examiner’s office removed the body of one victim, in a black bag, through the hotel’s east entrance.

“It’s such a shock,” said Gary Bates-Brown, 48, a hotel steward. “That’s really crazy.”

Earl Bolton, 50, a Hilton guest from Maryland, said he had spent time near the location of the shooting earlier in the day.

“It seemed quiet,” he said.

Kimball Hinton, 48, said he was in his hotel room at the Sheraton JFK Airport Hotel when he heard sirens around 12:30 p.m.

He and about 30 other Sheraton guests went to investigate, he said. “Once that started breaking out,” he said of the sirens, “everyone started breaking out.”

Mr. Bates-Brown said the area where the shooting occurred was typically quiet after breakfast. “That area is pretty much for waiting for the shuttle bus,” he said.