Overbrook High Lockdown Lifted After Police Investigation

PHILADELPHIA (CBS) -- Overbrook High School was briefly on lockdown after a teacher reported hearing a gunshot, Wednesday morning.

The high school located on the 5800 block of Lancaster Avenue was placed on lockdown, just before 9:30 a.m.

According to authorities, a teacher reported hearing a gunshot and a student says he saw another student run out of the school with a gun.

Police brought in K9 units and searched the entire school. The lockdown was lifted just before 10:30 a.m. after police said no weapon was found and no one was injured.

Detectives are investigating the possibility this was a fight outside of the school.