A 16-year-old boy has been arrested for allegedly concealing a firearm in his sock, which was then used by an acquaintance to shoot another teen on a crowded train in Queens, according to police and law enforcement sources on Thursday.

Officers from the NYPD’s Neighborhood Safety Team apprehended the teenager on Wednesday afternoon. They recognized him as a suspect linked to a shooting on an A train around 6 p.m. on Monday. This violent incident resulted in a 15-year-old victim being paralyzed from the waist down, authorities and sources revealed.

The teenager now faces charges including attempted murder, assault, and criminal possession of a weapon, police reported.

According to sources, the arrested youth had previously shot and injured the same 15-year-old in an earlier incident in February. During the recent incident, his companion allegedly retrieved the gun from his sock and shot the victim as the train neared the 80th Street station in Ozone Park.

Following the shooting, the duo made their escape while the victim, who suffered gunshot wounds to his neck and back, was transported to Jamaica Hospital Medical Center.

The victim’s mother, who prefers to be known only as Ms. Davidson, shared with The Post, “He’s paralyzed from the waist down. He had eight blood transfusions. Both of his jaws are broken. His lung and liver are pierced.”

The alleged shooter, seen in surveillance images released by the NYPD Tuesday, was still on the loose Thursday. 

The violence erupted when the victim recognized the now-in-custody 16-year-old from the February shooting, sparking a fight, sources said. 

The teen victim was shot in the leg during a dispute around 4:55 p.m. Feb. 7 on Everdell Avenue near Gateway Boulevard in Far Rockaway — and the alleged gunman was arrested 10 days later, the sources said. 

But the young victim suddenly became uncooperative and refused to provide testimony, so the district attorney’s office declined to prosecute the case, the sources said.