“It’s only going to get worse,” a veteran NYPD detective in Manhattan told the New York Post after a mass shooting in Harlem left a total of at least 20 victims shot citywide in fewer than 6 hours.

A young college basketball star, Darius Lee, 21, was killed while eight people were injured early Monday, signaling an ominous start to summer. “Unless the [Manhattan] DA starts enforcing these gun laws, this violence will continue, and it’s going to be total anarchy in the summer,” the detective added.

The incident happened near the intersection of East 139th Street and Fifth Avenue around 12:40 a.m. Monday at a music video shoot for rapper Rich Rhymer. According to the NYPD, Lee, who police said was not an intended target, died of his wounds after a dispute broke out between two groups, which led to the shooting to occur.

It wasn’t clear if any of the people involved in the video shoot was part of the deadly fight, officials said.

Responding officers found five people shot on a footpath just under the Madison Avenue Bridge, said NYPD Chief Brian McGee, commanding officer of Detective Borough Manhattan North, at a morning press conference.

The surviving victims were transported to local hospitals by EMS, McGee said. The four other victims were another 21-year-old man, a 22-year-old man, two 24-year-old men, a 31-year-old man, a 42-year-old man, and two women, 22 and 23, cops said.

“It’s Father’s Day weekend,” Police Commissioner Keechant Sewell told reporters early Monday. “It’s a weekend where people were supposed to be able to enjoy themselves with their families.”

“The emboldened individuals responsible for this are exactly who our officers are battling every day to make our city safe,” she said. Mayor Eric Adams said he was in Harlem until 2 a.m. after the shooting.

“We are going to continue to zero in on removing guns off the street,” Adams said. “We have removed over 3,000 guns thus far. We’re going to continue to go after those shooters, and I’m happy to hear that the court system is picking up some of these cases.

“But we have to move even further to ensure dangerous people go to trial and [get a] determination that they are guilty and serve time,” he said. 

Monday’s nine Harlem gunshot victims were among at least 20 people shot citywide between 8:45 p.m. Sunday and 2:30 a.m. Monday, law enforcement said.

Three people were shot on Taft Avenue near Westervelt Avenue in the Brighton Heights section of Staten Island around the same time as the Harlem mass shooting, authorities said.