The FBI has launched an investigation after a Twitter user made a death threat against Brick Township Mayor John Ducey.

Twitter user Daniel Roberts, going by the handle “Doctor Lock,” posted that it was “time to kill the mother[expletive], referring to Ducey, and posted his address.

The tweet comes in response to Ducey’s reaction to anti-Semitic comments made by another Twitter user. “The Big Kahuna” asked Ducey, “Can we please do something about our parks and beaches they are being invaded by the Hasidic and Orthodox Jews and being ruined. Our tax paying residents are being forced out while our politicians sit and do nothing.”

Ducey responded to the user, "Our parks security has started already. Just call police with any problems and they will send them out."

Some criticized Ducey’s response and felt that “send them out” referred to the Jewish population. They also felt that Ducey should have condemned the anti-Semitic language.

Ducey says that when he made reference to “them” he meant police officers.

Ducey told News 12 New Jersey, “The question posed started off in a very anti-Semitic comment. I didn't respond to those at all because I didn't want to inflame the situation. I didn't want to give credence to that actual opinion so what I did was I took the second part of his question. When he was asked what to do at a park I gave him the proper protocol. Call police and park security if there are any problems."

The “Doctor Lock” Twitter account that posted the threat against Ducey has been suspended.