Terminals in Newark Airport went on lockdown today. A Newark airport lockdown stopped flights in and out of Newark starting around 5 pm EST Sunday.

The cause? One man! Even stranger – he wasn’t caught!

The concern came at 5:20 PM EST when a man walked the wrong way down an exit ramp, reports local press. That prompted TSA to close screening. Then 2 1/2 hours later, TSA switched to rescreening everyone.

Why the delay? That’s not reportedly clear either. By 1 AM Monday morning, lockdown ended. It’s not clear why the lockdown took so many hours, why it was delayed initially 2 1/2 hours, and why the man couldn’t be found.

Reportedly “Continental announced that passengers scheduled to fly into or out of the airport on Sunday and Monday could reschedule trips without penalty. Officials estimated that thousands of people were affected.”