NEW YORK (CBSNewYork) — An attorney for the family of Avonte Oquendo said Tuesday that the autistic teen had tried to run out of school the very day before he disappeared.

Attorney David Perecman told 1010 WINS Avonte, 14, had gone through the same “runaway” routine on Oct. 3 of last year as he did the following day, when he ran out of the Riverview School in Long Island City, Queens and was never seen again.

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Perecman told DNAInfo that Avonte was with a group walking from the fifth floor down to the second when he ran off on Oct. 3. It was not clear whether Avonte was stopped by a teacher or staffer.

The incident was not in Department of Education Special Commissioner of Investigation’s report about the incident, but Perecman learned about it through NYPD documents he obtained via a Freedom of Information Act request, DNAInfo reported.

A day later, Avonte was seen on surveillance camera running out of his school, and was never seen alive again. Three months later, Avonte’s remains were found along the shoreline in Queens.

The report released last month by Special Commissioner of Investigation Richard Condon detailed the series of events that led up to Avonte’s disappearance from the school in October of last year. The report does not find one person responsible for Avonte leaving his school, but rather detailed a tragic chain of events involving several people.

On the day Avonte ran out of the Riverview School building, he was with 11 other students, a teacher, and two paraprofessionals when he was able to slip away – walking from the fifth-floor cafeteria to a second-floor classroom.

The report said a father waiting to pick up his sick child saw Avonte in the lobby, as did a school safety agent assigned there.

“Twice, (school safety agent) Perez called out ‘excuse me’ to the boy, but he did not respond,” the report said. “SSA Perez could not chase after the student because she was the only SSA at the main security desk and could not leave her post.”

The report said Perez had no idea Avonte left the building, although she remembered seeing him enter the stairwell and head upstairs, according to the report.

But one of the paraprofessionals noticed Avonte was missing.

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The agent told an assistant principal Avonte hadn’t left the building. That assistant principal then asked the principal in charge of the building to call for a “soft lockdown,” but the principal initially refused due to concern over alarming the students, according to the report.

The principal eventually ordered the lockdown after hearing that the safety agent wasn’t sure if the student she saw went back upstairs or left the building.

Meanwhile, the search for Avonte started, but Condon said by that time, Avonte was outside.

The report also said Avonte’s teacher had previously sent the teen home with a form which his mother filled out warning that her son might run, according to the report by the Special Commissioner of Investigation for the New York City School District.

Avonte’s mother, Vanessa Fontaine, wrote on the form “Safety concerns – Please make sure you keep an eye out he likes to run. Need 1-1 supervisor will leave the building.”

An intensive search for the missing teen ensued after he disappeared, and finally, his remains were found in the East River offshore from College Point in January.

The New York City Medical Examiner’s office could not determine how he died.

Avonte’s family has filed a lawsuit against the city.

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