A teacher’s aide at a high school in Rockville has been accused of failing to quickly report two autistic teenagers who went missing from the school, one of whom walked six miles in bad weather to get home.

The incidents happened Monday at Rock Terrace High School on Martins Lane.

Montgomery County Police said they have arrested and charged Alfredo Lopez, 59, of Gaithersburg with two counts of neglect of a minor in the case. He works as a teacher’s aide and is in a supervisory role at the school.

Officials with Montgomery County Public Schools said Lopez has been placed on administrative leave.

Both students were eventually found safe on Monday.

In one case, police said Lopez saw one teenager — a 16-year-old boy who has autism — walk away from the school in the morning around 9:52 a.m. but did not notify school staff members. Around 12:40 p.m., police said, Lopez told administrative personnel that the boy had left after a relative called about picking him up. At that point, the student was reported missing to law enforcement.

Alfredo Lopez has been charged with child neglect. He works as a teacher’s aide at Rock Terrace High School in Rockville. (Montgomery County Police)

That same day, police said, there was another incident involving Lopez.

Around 1:51 p.m., a bus driver for Montgomery County Public Schools saw the 16-year-old boy walking north on Ridge Road near Sweepstakes Drive in Damascus.

Then around 3 p.m., police got a call about another missing student — a 16-year-old boy who was nonverbal and had autism. Lopez was also responsible for overseeing the student, according to police.

In a statement, police said, he had “lost sight of the student and did not immediately follow established protocol to report the student as missing to administrative staff.”

A surveillance video at the school showed the teen leaving the school through the front door around 2:53 p.m. He was found around 6 p.m. that day at his home in the Glenmont area.

Police later figured out that the student had walked roughly six miles in bad weather from Rock Terrace High School to get home.

Lopez was arrested Wednesday at his home, police said.

In a Thursday letter to parents, Stephanie Schaufelberger, the acting principal, wrote that Lopez’s “alleged inaction is unacceptable.” County public school officials said he has worked at Rock Terrace since 1999 and before that worked for two years at Rockville High and seven years at Stephen Knolls schools as a teacher’s aide.

It was not immediately clear if Lopez had posted bond.