A teen who was supposed to be headed to jail on attempted murder charges in Brooklyn was accidentally released from custody early Thursday — after he was mixed up with someone else, officials said.

Shawn Singletary, 19, was arrested Wednesday for allegedly firing gunshots at a car in Brooklyn on Sept. 30, according to a criminal complaint.

He was arraigned in Brooklyn Criminal Court, where a judge ordered he be held without bail.

But then, “at 1:15 in the morning there was some kind of paperwork issue and he was [released on his own recognizance] apparently confused with someone else,” New York State Courts spokesman Lucian Chalfen told The Post.

Chalfen said Singletary was no longer in court custody at the time he was set free. The NYPD said the defendant was in the Department of Corrections’ custody, but the DOC insisted that he was not in its custody at any point leading up to his release.

Chalfen insisted the court system was not responsible for the bungle, but couldn’t say which agency was.

Police said Singletary was back in custody Thursday afternoon.

Singletary is also facing criminal possession of a weapon and reckless endangerment charges, according to the criminal complaint. He faces up to 25 years in prison if convicted on the attempted murder charge.

He has two other open criminal cases from January for alleged assault and robbery, court records show.

Singletary’s lawyer Calvin Simons declined to comment.

Additional reporting by Amanda Woods