Seven cops were assaulted last night after a fight broke out on a Brooklyn street — and some nearby belligerent residents threw bleach on the officers, police said.

The incident began when cops issued summons to two people in front of a building on Lexington Avenue in Bedford-Stuyvesant shortly before 7 p.m.

It wasn’t clear what the summonses were for, but a large crowd gathered and a scuffle broke out, injuring two cops, police said.

At that point, people inside the three-story building began throwing the bleach, striking five cops with it.

“I saw all these cops. I’ve never seen so many in one place — there must have been more than 30,” said a witness who didn’t want to give her name.

“I saw a woman get arrested — she had blood running down her face.”

Cops arrested five people involved in the fight, but no one who had thrown the bleach, police said.

Five cops were taken to Methodist Hospital, where they were treated for minor injuries.