A massive water main break turned a Brooklyn block into a flood-zone early Thursday, uprooting a tree and forcing at least 50 people to flee from their homes, officials said.

Water started shooting high into the air around 5 a.m., causing the evacuation of at least two apartment buildings along Pacific St. near Albany Ave. in Crown Heights.

Video from the scene shows a geyser erupting from the street and flooding the block, as officials from multiple city agencies work to get the gusher under control.

No injuries have been reported.