Washington Elementary School in Medford was briefly placed on lockdown Thursday afternoon after a report that an armed man was possibly seen running toward the school, police said.
Medford Police Chief Tim George said officers received a report that two men approached a house near the intersection of Catherine Street and Park Avenue and threatened a person there.
One of the men was reportedly armed, George said.
When the men neared the house, a dog bit one of them, and they ran away. They were last seen heading in the direction of the elementary school, so school officials placed the building on lockdown, which ended around 3 p.m.
A school official who answered the phone for comment said the students had been released and an email will be sent to parents describing the situation.
George said the search would continue for the suspects.