Three students are in custody after a security guard heard a gunshot inside a Philadelphia high school and police found a .45 caliber shell casing in a stairwell Friday afternoon.
Benjamin Franklin High School, located at 550 N. Broad Street, went into lockdown around noon, after an altercation in the stairwell.
Initially, school administrators said they did not believe a gun went off inside the school, but the security guard on scene told police he did heard a gunshot.
Philadelphia police took three students into custody and were searching for a weapon while doing a floor-by-floor sweep of the seven story building.
Benjamin Franklin High School enrolls over 600 students, down from over 800 in 2014. Close to 6 out of 10 students graduate. The school works to give students the skills to pursue one of three paths, according to the school's mission statement -- attend college, attend a 2-year technical program or trade school, military or the workforce.
According to the latest Philadelphia School District survey, 3 out of 10 students have a learning disability, and 100 percent of students are economically disadvantaged. As of 2015, 10.4 percent of grade 11 students scored "proficient" or better on the Keystone Algebra 1 exam, 14.9 percent in literature, and 5.4 percent in biology.
In 2014, the school reported 30 assaults.