CHICAGO (CBS)–Chicago now has more than 1,000 high-definition surveillance cameras at all nine Red Line subway stations and the city’s 12 Blue Line subway stops, the city said Thursday.

A ride-share tax that went into effect last year is funding a public transportation security upgrade that aims to improve safety at the CTA’s 145 train stations with new lighting and improved video surveillance systems.

Chicago police said HD capability at CTA stops has helped arrest an estimated 200 people each year.

CTA riders are always on camera thanks to 32,000 cameras that have been added to stations since 2011, according to the city, which said in a statement that Chicago has the most comprehensive public transit surveillance system in the U.S.

Since May of last year, 660 old analog cameras were upgraded and another 340 new cameras were installed, the city said.