At least two people have been killed in a vehicle attack and shooting near the 9/11 memorial site in New York, according to Sky sources.
Witnesses told local media a vehicle drove down a popular bike path and struck pedestrians and cyclists before the shooting started.
Law enforcement sources confirmed two deaths to Sky News and said a number of people had been injured, warning commuters to expect many emergency services workers in the area.
A large number of police vehicles could be seen near West Street and Chambers Street, which is near a community college, a high school and a few blocks north of the 9/11 memorial site, where the World Trade Center once stood.
Photos from the scene showed a badly damaged white rental pickup truck in the middle of the road.
A 14-year-old student from the nearby Stuyvesant High School told the New York Post: "What happened was there was a car crash… he came out of one of the cars. He had two guns.
"He was running around Chambers and somebody started to chase him.
"I heard four to six gunshots – everybody starts running."
NYPD said one person had been arrested and they were not looking for anyone else.
Sky News US Correspondent Hannah Thomas-Peter said: "It is not clear whether they are treating it as a terror-related event."