A lawmaker says a spate of recent deaths on New York City subway tracks should be “a wake-up call to our transit system.”

City Council Transportation Committee Chairman James Vacca made the remark at a hearing Thursday on safety in the nation’s busiest subway network.

The Metropolitan Transportation Authority runs the subways that carry 5 million riders on an average weekday. Officials say they’re working toward testing barriers on platform edges and technology that sounds alarms when someone or something is on the tracks.

The subway drivers’ union has suggested lower speed limits for trains entering stations. The MTA says that would lengthen commutes and make platforms more crowded.

Fifty-five people died last year after falling, jumping or being pushed onto the tracks. Two recent pushing deaths have drawn attention.