Nearly two weeks after a violent robber began attacking Asian residents of East Harlem, the authorities arrested a man on Tuesday aboard an interstate bus in southern New Jersey.

The Police Department had made catching the robber one of its priorities, deploying additional officers into the neighborhood, assigning Mandarin- and Cantonese-speaking officers to talk to people in the community and papering the area with fliers in multiple languages. They identified Jason Commisso, 34, as a suspect over the weekend.

The string of mostly daytime crimes followed a brutal pattern, the police said: a single robber would follow men and women — all of Asian descent, most over 40 — as they entered apartment buildings. He then shadowed them into elevators, where he would repeatedly punch them in the face before making off with their belongings. At least eight people have been attacked, the police said.

The apparent singling out of one ethnic group led to the involvement of the department’s hate crimes unit, though Commissioner Raymond W. Kelly cautioned late last week that it had not yet been established that the robberies were hate crimes.