School officials implemented a "lock-in" at Derby Middle School late Monday morning after a concern arose over a message scrawled on a bathroom stall, according to the superintendent.
Supt. Matthew Conway said in a statement that the message was discovered around 11:45 a.m. Monday. A precautionary lock-in went into effect while police were called to the scene to investigate.
Students were safe and police gave the "all clear" by about 2:40 p.m., when all school activity returned to normal, according to Conway.
