Thousands of Westchester police officers have been told to stop all law enforcement activity in New York City. 

News 12 is told that the Affiliated Police Associations of Westchester is concerned that a new set of police reform laws in the city stops Westchester police officers from doing their jobs. 

The group represents around 4,000 police officers across more than 40 municipalities in the county. 

Officers in Westchester, particularly those who boarder the Bronx, say they find themselves in the city at some point. News 12 is told some officers go to the city for investigations, warrants and traffic stops. 

On Wednesday, Mayor Bill de Blasio signed the NYPD Accountability Package to increase transparency between the city department and the public. 

Part of the new law bans certain arrest techniques New York police officers are trained to use. This includes the legal kneeling or sitting on the back, bottom, or chest of a suspect.

News 12 is told the police in Westchester fear they could be criminally or civilly liable if they enforce the law in New York City, even if it's a lawful arrest.