2 Arrested in Threats to New York Jewish Community, Police Say

The authorities arrested two people on Saturday at New York’s Pennsylvania Station and seized a large hunting knife and an illegal firearm with a 30-round magazine in what they described as a “developing threat to the Jewish community.”

The New York Police Department was “strategically deploying” resources to “sensitive locations” throughout the city based on the threat, Keechant L. Sewell, the police commissioner, said in a statement.

Commissioner Sewell did not elaborate on the nature of the threat or provide any information about the people who were arrested.

Two law enforcement officials with knowledge of the situation said threats about violence to Jewish sites, including “shooting up a synagogue,” were recently made in social media posts and there was a reference to a violent act occurring on Friday.

One of the officials said the additional deployments in the aftermath of the arrests were precautionary and not because of any further specific threats.

Commissioner Sewell said that a joint-terrorism task force of the Police Department, Federal Bureau of Investigation and other investigators uncovered the threat on Friday and “moved swiftly to gather information, identify those behind it and operationally neutralize their ability to do harm.”

The authorities issued an alert late on Friday in which they identified a man they said had made recent threats to synagogues in the New York area.

They said the man, Christopher Brown, has a history of mental illness and recently expressed an interest in coming to New York City to buy a gun.

A law enforcement official said Mr. Brown was one of the two people arrested in Penn Station on Saturday. The police did not publicly identify the second person who was arrested.

Commissioner Sewell said “sharp-eyed M.T.A. police officers” arrested the two while they were entering Penn Station.

William K. Rashbaum and Chelsia Rose Marcius contributed reporting.