New York UPDATES: Six injured including cop as gunman opens fire

At least six people - including one police officer - have been shot after a gunman opened fire in Midtown Manhattan on Tuesday evening.

Scores of people have been evacuated from homes and businesses following the shootings, most of which happened in a skyscraper housing several big businesses including the NFL, Deutsche Bank, JPMorgan Chase and the Blackstone Group.

People across the neighbourhood - which is now on complete lockdown - have been warned to be vigilant and "stay safe" amid the threat, meanwhile the New York City Police Department has told local media the investigation is moving at pace.

There are currently unconfirmed reports that the gunman has barracaded himself inside a building and is wearing a bulletproof vest.

In addition, Helicopters have been seen swarming Midtown Manhattan. However at this time the nature and extent of any injuries are unclear.

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