A teacher’s aide from a New York school for students with special needs was arrested after she brought a loaded gun to the school on Wednesday and prompted a lockdown, police said.

Gillian Jeffords, 24, of Warwick was hit with a felony charge of criminal possession of a weapon on school grounds after her black 9mm Ruger was found by a colleague inside her handbag in a classroom closet at the Jesse J. Kaplan School in West Nyack, authorities said.

Clarkstown Police Department spokesman Pete Walker told reporters that when the gun was found around 9 a.m., “the room was not occupied by students.”

The staffer who found the weapon immediately notified the school principal, who put the school on lockdown.

The school police resource officer ultimately secured the gun “and ensured there were no further concerns for students’ safety,” police said.

Cops were called to the Rockland County school and Jeffords – who has a full carry permit and valid firearms license in both New York and Pennsylvania – was taken into custody without incident.

She was suspended from her post at the school with pay and both of her weapons licenses were confiscated by police.

Jeffords, a new hire at the school, never took the gun out of her bag and it was “never used in a threatening manner,” police said.

It was not immediately clear why the aide brought the gun to the school, which serves students ages 5 to 21 with “autism, cognitive disabilities, medical fragility and/or multiple disabilities,” according to its website.

Jeffords was released on her own recognizance at a court appearance Wednesday. Her next court date was scheduled for May 7.

Mary Jean Marsico, the chief operating officer of the Rockland Board of Cooperative Educational Services, said at the press conference: “To the parents and our staff, we assure you at no time was anybody in harm’s way – we assure you.”

A school spokesman said that there was never “anything alarming” that had previously been mentioned about Jeffords.”

The incident comes after President Trump called for arming qualified teachers and staffers to prevent mass shootings in schools in the wake of the Feb. 14 South Florida high school massacre that left 17 dead.