New video obtained by NBC 4 New York shows 14-year-old Avonte Oquendo bolting out a door left open by an adult at his Queens school the day he disappeared.
The video shows the door failing to close after the adult leaves the school's Center Boulevard exit at 12:07 p.m. on Oct. 4. It stays open for about 30 minutes and then Avonte is seen dashing through that door at 12:38 p.m.
Just minutes later, a school safety agent comes by and closes the door at 12:41 p.m., but he is already gone. Avonte is believed to have headed toward a park along the East River near his school, and was never seen again.
The timeline of his last moments at the school was previously known, but the footage that emerged Tuesday has never been seen publicly.
His disappearance launched a search that extended citywide and beyond, and captured the attention of the nation.
The search came to a tragic end this month when parts of his body were found along the East River, about 9 miles by waterway from his school.
His funeral was held over the weekend.
Investigators are still trying to determine how Avonte died, and further tests are needed to determine the cause and manner of death, officials have said.
The family's lawyer, David Perecman, filed a notice of claim in October, the first step in suing the city, and has publicly listed a number of mistakes he alleges contributed to the boy's disappearance and what he has described as a flawed search effort.
The city's law department has called the boy's death a tragedy and said its attorneys will review a lawsuit when it's filed.
The Department of Education had no immediate comment. The NYPD said the matter is under investigation and it could not comment because of pending litigation.