The Associated Press reports:
BARNEGAT, N.J.--It's the case of the nonexistent ninja. Public schools in Barnegat were locked down briefly after someone reported seeing a ninja running through the woods behind an elementary school.
Turns out the ninja was actually a camp counselor dressed in black karate garb and carrying a plastic sword.
Police tell the Asbury Park Press the man was late to a costume-themed day at a nearby middle school.
The lockdown began shortly after 9 a.m. Wednesday and lasted until 9:30.