Superintendent Elizabeth Jewett said the lockdown was put in place out of an "abundance of caution" in accordance with district policies and procedures.
A 30-year-old county worker was critically hurt and a 43-year-old worker was sent to the hospital after the crash Monday in Warren Township, police said.
Prosecutors say two men and a woman made a massive, phony withdrawal at a Somerset County bank. They say one of the men then rammed a police car, got out and physically struck an officer.
The photo was circulated on social media this week showing a white male wearing black makeup standing next to another white student dressed up in a cowboy hat and whip.