A tour helicopter hit a small plane and both crashed outside Hoboken, New Jersey with debris falling into the Hudson River, police reported on Saturday.
There was no immediate report on casualties. CNN said the helicopter had six people aboard.
Search and rescue crews were in the area, which is just across the Hudson from New York City. Fox TV said one survivor had been pulled from the river.
Helicopter carrying six collides with plane over Hudson River
The helicopter was operated by Liberty Tours, local media said.
In January, a US Airways jet with more than 150 people on board crashed into the frigid Hudson River off Manhattan after apparently hitting a flock of geese. All aboard survived.