Updated

Residents of a swanky Upper East Side high-rise have 24-hour gated entry, a heated indoor pool, breathtaking views of the river — and bullets whizzing through their windows.

A mystery gunman is shooting up apartments at One East River Place from clear across the water on Roosevelt Island, law enforcement sources told The Post.

Now its residents are terrified.

“I’m petrified for my life,” exclaimed Ilene Epstein, 55, who lives in a river-facing apartment on the 22nd floor of the 50-story rental building between East 72nd and 73rd streets.

“I moved into this apartment because of the river. I have beautiful views,” said Epstein, a real estate agent. “[But] I’ll move out of my building before I walk around with a bulletproof vest.”

The first bullet crashed through the living-room window of a 14th-floor apartment in the building, whose address is 525 E. 72nd St., sometime overnight between Thursday and Friday, police sources said.

The tenant awoke Friday morning to find the living-room floor strewn with glass. Cops found a .38-caliber bullet, most likely fired from a Smith & Wesson handgun, sources said.

Less than 24 hours later, another bullet pierced the window of a unit on the 32nd floor of the building, where two-bedroom apartments can rent for more than $7,000 a month.

This time, the apartment’s tenant was jolted awake at around 1:15 a.m. Saturday by the shattering of the living-room window. Police sources said no ballistic evidence was immediately recovered in that incident.

Neither tenant was injured, but they easily could have been.

“They were lucky they weren’t up late watching television,” a law enforcement source said.

Cops were puzzled by the source of the gunfire until they realized the timing of the second shooting matched up with two 911 calls reporting shots heard coming from another apartment building — about 1,400 feet across the East River on Roosevelt Island, sources said.

Investigators “think it’s some a–hole standing on a balcony shooting across the river,” a high-ranking NYPD insider said.

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