Elmwood Park High School was placed on a temporary lockdown Friday morning after a contractor for the school district was mistaken for an intruder.

Two staff members “saw a then unidentified adult male” in the school, 8201 W. Fullerton Ave. in Elmwood Park, and reported him to administrators, according to a letter sent to parents by Dr. Nicholas Wade, superintendent of Elmwood Park Community Unit School District 401.

The school was put on lockdown and four other district buildings were placed on a soft lockdown, according to Wade.

The man was later “identified as an employee of a contractor the District is currently using and did not pose a threat to school safety,” Wade wrote.

The lockdown was lifted and classes resumed for the remainder of the day.