Mayor Bill de Blasio and Police Commissioner Bill Bratton announced at a news conference Wednesday the expanding presence of NYPD police officers on subway trains due to an uptick in slashings.

Bratton says the NYPD will be expanding its presence in subways and on subway cars, especially late at night.

He says the NYPD is well equipped to take on the challenge of policing the subways due in part to new and advanced below-ground radios that police have already begun using in the Bronx. Bratton says policing subways was difficult many years ago because of limited range in radio service.

"Not only do we have to keep people safe, we have to make sure that they feel safe," says NYPD Chief of Patrol James O'Neill. "By people seeing uniformed cops in the system, they feel safe."

Brooklyn Borough President Eric L. Adams, a former NYPD police captain of 22 years, commented by saying officers used to rely on the sounds of train conductors' horns, the tapping of a falling night stick and other unconventional methods of communicating with each other below ground.

Overall, Bratton says violent crimes are down on the subway.