NEW YORK (CBSNewYork/CBS News) — The FBI is warning NYPD and law enforcement nationwide about a possible Halloween attack against police officers by an anarchist group, an official told CBS News.

A group known as the National Liberation Militia may be planning to cause a disturbance and attack officers who respond, CBS News reported. The group reportedly recommended members wear masks and bring weapons, such as bricks and firearms.

There is no specific threat to New York City and police are monitoring the situation, NYPD officials told the New York Post.

In a statement, the FBI said Tuesday: “As part of the continuous dialogue with our law enforcement partners, the FBI routinely shares information about potential threats to better enable law enforcement to protect the communities they serve. We urge the public to remain vigilant and report suspicious activity to law enforcement.”

Anarchists infamously were blamed for being the main instigators in the 1999 “Battle of Seattle” during a World Trade Organization meeting.

In an interview with Scott Pelley for “60 Minutes,” one of the anarchists associated with that incident said: “We want to pose a credible threat to the biggest, most powerful people in the world.”