OMAHA, Neb. -- Omaha law enforcement moved quickly Monday to make an arrest in an online school threat. 

It's an investigation that involved both the Omaha Police and the FBI. Millard Public Schools confirmed the threat Monday. 

The school's principal said law enforcement was able to trace the message back to the sender and that person is part of the Russell Middle School community. 

Police made the arrest Monday. The principal said police determined there was no actual concern for safety at the school.