Singer Josh Groban tweets from near scene of New York attack

US singer Josh Groban has tweeted from near the scene of the New York rampage that has killed at least eight people and injured 12.

A pickup truck ploughed into pedestrians and cyclists as it drove 20 blocks along a bike path near the World Trade Centre site in Lower Manhattan, around 3pm local time on Tuesday. Several people were struck.

The driver then got out of the vehicle and brandished replica guns before being shot in the leg by police and then arrested.

Posting on Twitter, Groban said he was with his dog half a block away from the rampage when he heard “8-10 quick rounds” fired.

Singer Josh Groban was "half a block" from the deadly rampage. (Getty Images)

“That’s the corner I was supposed to have my coffee but my dog pulled me into the park half a block away 10 min before shooting,” he wrote.

Once he was away from the site, Groban captured footage of the response from New York’s fire and police departments, hailing them as “amazing”.

"Devastated for the victims and their families tonight & inspired by the spirit of this city. Sirens and trick or treaters everywhere," he later wrote.

Law enforcement officials told the New York Times the suspect was heard yelling “Allahu Akbar,” Arabic for “God is great”, after getting out of his truck.

Witnesses reported hearing multiple gunshots and seeing bodies and bicycles strewn along the road.