NEW YORK -- Six teenagers were injured in a shooting outside a party venue in New York City early Sunday, police said.

The gunfire erupted at around 1:00 am local time after a birthday party ended at an event space in the Cypress Hills neighborhood, Brooklyn, a spokesperson of New York City police said.

The wounded, aged 15 to 17, were taken to hospitals and are all in stable condition, police said.

Jessica Tisch, New York Police Department commissioner, told a press conference that security camera footage showed two unidentified men walking toward the venue before opening fire on the crowd.

"Both individuals displayed firearms and discharged multiple rounds toward a crowd gathered outside the venue," she said, adding the suspects then fled on foot.

Tisch said that the exact motive is currently unknown but it appears to be gang-related.

Investigations are underway, police said.