Disturbing video released by the New York Police Department Monday shows a woman getting up from a bench and shoving another woman into a moving subway train entering a Times Square station during the early morning rush hour commute in what’s believed to be an unprovoked attack.

The female suspect, whom police describe as a woman in her 30s wearing a multicolored scarf, black shirt and beige pants, is seen getting up from a bench inside the 42nd Street and Seventh Avenue station and suddenly shoving a 42-year-old woman, who is off camera.

Video shows it happened as a northbound No. 1 train was speeding into the station. The assailant then appears to calmly walk away, as several other bystanders on the platform appear relatively unaffected. Police say the 42-year-old woman did not fall onto the tracks, but rather the force of the push knocked her into the moving train before she ricocheted backward onto the platform.