At least eight people died and 15 others got injured after an attacker drove a rented truck onto a bike path near the site of the World Trade Center memorial in Manhattan on 31 October
However, officials were still working to assess the extent of the casualties.
According to the New York Times, the authorities said that after crashing the vehicle, the attacker got out of the truck with two fake guns before being shot by police officers.
New York City Mayor Bill de Blasio said at a news conference, "Based on information we have at this moment, this was an act of terror, and a particularly cowardly act of terror aimed at innocent civilians."
A senior law enforcement official said that the Federal authorities were treating the incident as a terrorist attack.
"He jumped out of the truck with a pellet gun, yelled, 'Allahu Akbar,' and the First Precinct lit him up," a law enforcement official said.
Several nearby buildings, including Stuyvesant, were placed on lock-down.
Earlier, reports came out that police are responding to reports of gunfire. According to a tweet posted by New York Police Department, one person was taken in custody. NYPD further advised public to avoid West Side Highway Area.
Currently there is one person in custody. No others outstanding. All information is preliminary as the investigation is ongoing. pic.twitter.com/nsaUgZ8MJH— NYPD NEWS (@NYPDnews) October 31, 2017
"Currently there is one person in custody. No others outstanding. All information is preliminary as the investigation is ongoing," the NYPD tweeted.
A large number of police vehicles were seen in Manhattan near West Street and Chambers Street.