NBC4 New York is reporting that an "all-clear" has been given after a suspicious package prompted an evacuation of LaGuardia Airport's central terminal.

The package was found near a phone booth and had protruding wires, WABC sources described.

CNBC tweeted: "According to Port Authority Public Affairs, the suspicious package at LaGuardia turned out to be a lighting ballast with wires sticking out."

[blackbirdpie url="https://twitter.com/BloombergNews/status/324181496502030337"]

Twitter users began posting photos of stranded travelers standing outside with their luggage almost immediately.

Cities across the country have seen heightened security since two explosions killed at least three people and injured 170 others at the Boston Marathon Monday.

Business Insider has scoured social media for purported photos from the scene:

(Photo: Twitter/@RhinoB)

(Photo: Twitter/@davehjoo)

(Photo: Twitter/@grahamstan)

(Photo: Twitter/@WahWhoWah)

​This is a breaking news story. Updates will be added.