Police are investigating threats made against officers on New Year's Eve. View Full Caption DNAinfo/ Sybile Penhirin

NEW YORK CITY — The NYPD is investigating several threats to kill NYPD officers during New Year’s Eve celebrations, DNAinfo New York has learned.

Sources say there are several gang members on social media calling for New Year’s Eve to be “Kill a Pig Night” so that it will become “The New Year’s Eve Massacre 2014.”

SIGN UP FOR OUR NEWSLETTER FOR MORE NEW YORK CITY NEWS

The threats primarily come in tweets baring a host of vicious anti-NYPD hash tags including #@deadcopseveryday, #onlydeadcops, #wingsonpigs and #laughatyourdeaths, according to law enforcement sources.

One tweet reads: "Dear Police, Don’t think this cant happen again” accompanied by a photo of armed Blank Panthers from the 1960s and 1970s, sources say.

Approximately 15 arrests have been made as result of the threats, NYPD Commissioner Bill Bratton said at a Times Square press conference.

"Any threat against my officer is going to be dealt with very quickly, very effectively," he said. "We're not going to let any of them go by the board."

Police officials say the NYPD is on high alert, particularly in the wake of the Dec. 20 murder of NYPD officers Rafael Ramos and Wenjian Liu. Their assassin, Ismaaiyl Brinsley, took to Instagram that morning announcing he was coming to New York to kill police officers.

Sources say the NYPD has received 63 threats since the shootings and there have been 16 arrests connected to them.

There are presently 23 open investigations into threats against NYPD officers, a source said.

In addition to the deadly threats, various radical organizations are also calling for protests to disrupt the New Year’s Eve celebration, but the NYPD says it is prepared to safeguard the millions of revelers and protesters' rights to demonstrate.

Additional reporting by Ben Fractenberg.