A 19-year-old man is charged with the attempted murder of a New York City high school student.

The shooter, who allegedly shot and killed a 17-year-old boy outside his Upper West Side high school, causing an explosion of gun violence in possible retaliation, has been charged with attempted murder, police said Wednesday.

Police said Cheik Coulibaly, 19, was arrested shortly after the shooting broke out around 9:50 a.m. Tuesday at the corner of Amsterdam Avenue and West 68th Street.

Coulibaly, who was released on bail in an armed robbery case in 2021, allegedly shot the young victim multiple times in the torso, police said. The teenager had to undergo surgery but was expected to survive.

According to authorities, the bloodshed was due to an argument that started two blocks north of four or five teenage boys.

After the shot, the victim staggered to his school, Maxine Greene High School for creative investigations, police said. This school, in addition to nearby LaGuardia High School of Music, was closed following the shooting.

Meanwhile, Koulibaly left in a yellow cab he hailed, but savvy bystanders alerted the police, who were able to stop the cab a block away and arrest him.

“The taxi was heading downtown,” said the doorman who watched the arrest near 165 West End Avenue. There were about five police cars there. They cornered the cab at the back and front. The police came out with weapons at the ready and ordered the guy to leave. He got out and was arrested.”

In addition to the attempted murder, Koulibaly was charged with assault, criminal use of a firearm and criminal possession of a weapon, police said. On Wednesday, he was awaiting arraignment.

Koulibaly has three previous arrests, patrol chief John Chell told reporters on Wednesday. That includes two drug arrests in the Bronx this year and an armed robbery with a firearm that he was charged with in 2021 in Manhattan.

Records show that he posted $50,000 bail in November in an ongoing case. His next trial is set for April 18.

Just over three hours after the Upper West Side shooting, a 16-year-old boy and a 27-year-old innocent bystander were gunned down on East 129th Street and Madison Avenue in what police sources say is a possible retaliation.

The teen and four other Harlem Renaissance High School students were about to have lunch around 1:00 pm when three men approached them and a fight broke out, police said.

Bullets were fired during the fight, resulting in a teenager who sources say was on his first day of school, being shot in the leg.

A passer-by was also shot in the leg and taken to a Harlem hospital, police said.

Three suspects in the shooting fled, police said. Police believe the intended target was a teenager and say the shooting was gang-related.

A third incident involving reports of gunshots at East 105th Street and Park Avenue around 3 p.m. is also believed to be related, police said.

Four shell casings were found at the scene, but no one was injured.

No arrests were made in these cases.

“In the last five hours, we’ve had three shootings in northern Manhattan,” Chell said at a press briefing in East Harlem on Tuesday.

“Right now, we’re acting like they’re all connected,” he added. “Why do I say that? Due to the proximity, the geography, around the schools, the age of our victims, and now we’ve confirmed at least one incident, this incident here is gang-related.”