Daniel Enriquez, 48, a Goldman Sachs investment researcher, was shot once in the chest at about 11.42am on Sunday as he rode a Q-line train over the East River from his home in Park Slope, Brooklyn, into Manhattan, to have brunch.
Police later said that the attack had been unprovoked, and that the gunman was still at large having fled from Canal Street station in lower Manhattan wearing a Covid mask and dark blue hoodie.
Overall, New York is vastly safer than it was in the notorious 1980s and 1990s, when at its peak murders exceeded 2,000 a year compared with fewer than 500 last year.
But that offers Adams, a Democrat who on 1 January succeeded two-term fellow Democratic party mayor Bill de Blasio, relatively little comfort as he struggles to establish his new mayoralty, now in its fifth month.
Through many of these challenges, the mostly underground, vast subway train system runs as a common factor.
The perception of a crime problem has been heightened by recent shocking cases of crimes in the subway system, including a woman killed when she was pushed by a homeless man in front of a train in January, and the mass gun attack last month on the N train in Brooklyn in which 10 people were shot and 13 injured by a sole shooter, though nobody died.
The latest attack comes at an awkward moment for Adams. He has been working hard in recent weeks to get the city moving again, calling for businesses to reopen their offices and workers to return to their desks.
In March he went to the headquarters of Goldman Sachs, the employer of the rider slain on Sunday, to encourage the revival of in-person working which is still well below pre-pandemic levels in midtown and downtown. City authorities have projected that office vacancy rates across the five boroughs will remain at 20% over the next four years.
One essential piece in getting the city back to work is to lure New Yorkers back on to the subway. But rider figures are still at about 60% of their pre-pandemic numbers, creating a vicious circle in which the eeriness of relatively unpacked subway carriages and platforms further discourages people from returning to public transport.
