New York:  A helicopter has crashed in New York City's East River, killing at least two people, and emergency divers were in the water around the partially submerged aircraft, according to officials.

Eric Phillips, a spokesman for Mayor Bill de Blasio, said in a post on Twitter there was "at least one survivor, at least two fatalities. Divers are still in the water."

The Federal Aviation Administration said the Eurocopter AS350 went down near the northern end of Roosevelt Island at about 7 pm on Sunday (US time) and was reported to be upside-down in the water. The agency said it was investigating, and the National Transportation Safety Board would also probe the incident.

Video apparently of the incident filmed by an onlooker and posted on Twitter showed a red helicopter descending toward the water at dusk, then landing with a large splash before tipping onto its right side, its tail lights still flashing.

Xinran Jiang, who lives on Roosevelt Island with her husband, said they saw a red helicopter rapidly descending near the north end of the island at 7:08 pm (Eastern time).