A social media user threatened Times Square with two pounds of explosives, sparking a “full-scale” investigation by local, state and federal authorities on Sunday.

“The bomb threat made against Times Square is a despicable and cowardly act meant to instill fear and panic in our community, and New Yorkers will not tolerate these scare tactics,” Gov. Andrew Cuomo said in a statement Sunday.

The threat, which the NYPD said was not believed to be credible, was made on Reddit by a user who warned people to avoid Times Square because he was heading to the Crossroads of the World with two pounds of explosives, police sources told The Post.

It was unclear when the post was made, and it could not be found Sunday morning, suggesting it was removed by the website.

“There are no credible threats at this time, and these events will continue to be closely monitored,” a spokesman for the NYPD said.

The governor ordered state police to work with local and federal authorities “to launch a full-scale investigation into this incident.”

Police will increase patrols in Midtown on Sunday, officials said.