The Metropolitan Transport Authority is installing security cameras in all of New York City's subway cars, officials announced on Tuesday.
New York Governor Kathy Hochul said the cameras would make riders more confident in the safety of the transit system.
The plan is to install two cameras in each of the 6,355 subway cars, building on a pilot programme in which cameras were installed in 100 cars. The work should be completed by 2025, the agency said.
The agency is spending $3.5 million on the installation and the remaining $2m needed is through a grant from the US Department of Homeland Security's Urban Area Security Initiative.
There are already security cameras in the subway system's more than 470 stations, though they do not always work.
Tuesday's announcement came five months after a man started shooting passengers on a subway train in Brooklyn, striking 10 people in a highly unusual attack.
All survived their injuries, but the police search for the gunman was hampered by problems with the security cameras in the station.
An agency representative declined to say who made the cameras used in the pilot programme or whether the vendor would continue to be used in the expansion.
The New York Civil Liberties Union said the transport agency was being unduly secretive about surveillance and had given no information about how the camera data would be analysed and stored, and no evidence that expanding the use of cameras improves safety.
“Living in a sweeping surveillance state shouldn't be the price we pay to be safe,” Daniel Schwarz, an NYCLU technology and privacy strategist, said in a statement.
Ridership on the subway plummeted after the Covid-19 pandemic spread through the US in 2020, but has been gradually rebuilding to about 3.7 million rides on a typical weekday.
There have been more than 390 robberies on the subway so far this year, compared to more than 320 in the same period in 2019, police data show.
Danny Pearlstein, a spokesman for the transit advocacy group Riders Alliance, said there were more pressing areas of investment.
“Ultimately, the governor should also make a targeted investment in more frequent public transit service to cut platform wait times and attract more people to the system, creating safety in numbers,” he wrote in an email.