Hamden High School was placed in a lockdown early Thursday morning.
According to police, the lockdown took effect shortly before 7 a.m.
It was lifted shortly before 8 a.m., according to dispatchers.
School officials said a staff member informed the school administration that an unidentified male was in the buildings.
They said that's when the lockdown was initiated.
Police said an employee was walking down a hallway when she saw a student running toward her with a raised fist.
An investigation revealed that the person never intended any harm, threat or disruption.
Hamden Public Schools said it has safety procedures and protocols in place to ensure the safety of students and staff. It called what happened on Thursday a misunderstanding.
Further investigation found that a student running toward an employee was "making basketball type moves." When the employee turned around, the student was pretending to "dunk a basketball."
Hamden High School students were transferred to another location for the lockdown.
Officials said they were happy to report that no one was ever in any danger.
"We want to thank the entire Hamden High community, particularly our students and staff, for their quick and orderly response and cooperation," said Karen Kaplan, Hamden Public Schools.
Students have since returned to class.
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