A Hays CISD campus-based security monitor resigned after they allowed several Hays High students to enter campus before school hours to conduct an unauthorized senior prank.

Tim Savoy, Hays CISD public information officer, said the incident occurred in the early morning hours before school on May 24, which was the day after a supervised and authorized prank was conducted on Hays High principal David Pierce.

Savoy said four to six students were given keys by the campus-based security monitor to ent...