Workers returned to 345 Park Ave., on Monday​ under the watchful eyes of NYPD officers and a surplus of security after the NYC mass shooting.

During evening rush hour in New York City on Monday, a man calmly walked into a Park Avenue office building lobby and killed a police officer, then opened fire on other innocent strangers.

Family, friends, coworkers, religious leaders and more gathered for a prayer service for the Midtown mass shooting victims of last week. FOX 5 NY's Sharon Crowley reports from the Midtown service and speaks with members of the community.