A teen who had just gotten off work at a Shake Shack in Manhattan was hunted down in the subway system by a group of attackers who beat and stabbed him repeatedly, leaving him with six deep puncture wounds, police said Sunday. The 17-year-old was in the subway at East 53rd Street and Lexington Avenue in Midtown around 4:30 p.m. Saturday when the group of about six people clad entirely in black, including face masks, pounced on him. The attackers, who had gone to the teen’s job asking where he was, entered the subway station in pursuit of him and approached the victim on the northbound 6 train platform, police said. The attackers then punched and kicked the teen about the head and body. One of them pulled a knife and stabbed him multiple times. He needed to get staples to close six of the wounds.