Two groups of male teens had argued before the shooting, which sparked masses of festivalgoers and shoppers to run for cover, according to a police report.

Video obtained by CBS News Chicago shows the 19-year-old being transported on a stretcher out of the department store.

The 19-year-old woman was shot in the leg while walking with a group of people near Washington and State, outside Macy’s . This was just hours after thousands of people poured into the area for the Mag Mile Lights Festival and Parade.

The attack sparked masses of festivalgoers and shoppers to run for cover Saturday night when a woman stumbled into Macy's with a gunshot wound, Chicago police said.

On Saturday, police said a 19-year-old woman was walking on the sidewalk near the intersection of State and Washington streets shortly before 9 p.m. Police told Ald. William Conway (34th) that a juvenile suspect was in custody Sunday evening in connection with the incident,