AN active shooter unleashed chaos in broad daylight in the heart of Manhattan, leaving a police officer and a civilian fighting for their lives.

The gunfire erupted inside a swanky skyscraper on East 52nd Street between Park Avenue and Lexington Avenue on Monday — home to corporate giants Blackstone and the NFL.

A crazed gunman clad in a bulletproof vest and carrying an assault rifle stormed the building before barricading himself inside, law enforcement sources told the New York Post.

In footage captured by Fox 5, officers were seen carrying a bloodied victim while others tended to a person lying on the ground outside.

Witnesses reported hearing gunshots echoing through the area around nearby 51st Street and Park Avenue.

One told the NY Post: “It sounded like a barrage of shots …Like an automatic weapon. Like a high-capacity weapon.”

A heavy police presence quickly flooded the block as officers from both the NYPD and the Sheriff’s Department arrived in tactical gear with weapons drawn.

At least one police officer was shot in a shootout with the gunman and is in critical condition, senior law enforcement officials told NBC News.

Another civilian was also shot and remains in critical condition.

According to reports on X, the terrifying attack prompted a Level 3 mobilization, one of the highest alerts, bringing in counter-terrorism units, a bomb squad, and a heavy weapons team.

Emergency medical units were seen rushing to the 44th floor, while reports suggest the suspect may have barricaded himself on the 32nd floor.

The NYPD has urged the public to steer clear of the area as the situation remains active.

The force said in a post on X: “Expect emergency vehicles & delays in the surrounding area.”