Police are investigating a threatening phone call made to Middletown High School that prompted a lockout today, complete with swarms of armed officers and canceled after-school activities.Police say an unidentified caller indicated a gun could possibly be involved. They say they're also looking into a report that the caller may have mentioned being bullied. Neither police nor school officials have said the specific threat that the caller made. At the school today, no one was allowed into or out of the building. Parents who came to pull their children out early were turned away by police.Officials say two students who ignored the lockout and left school anyway were arrested for disorderly conduct.

Administrators say school will return to normal tomorrow.