An online threat that prompted Harrison school officials to put emergency procedures into effect at all district schools this morning was a case of mistaken identity.

Harrison School District Superintendent Dr. Louis Wool says there was a threat of violence at the high school later this week.

It was posted on social media.

As a precaution, all Harrison schools went into lockout, which means teaching and learning continued in school but no visitors were allowed inside the school and students had to remain indoors. Harrison police increased presence at all schools.

Some parents tried to pick their kids up from the high school during the lockout but they were turned back.

However, it turns out it was the wrong Harrison High School. The district said in a statement, "The Harrison Police Department has confirmed that the anonymous threat reported earlier today concerned Harrison High School in Evansville, Indiana, where an arrest has been made in this case."

The lockout was lifted shortly after noon.