A Herbert H. Lehman High School student faces charges for allegedly bringing a gun to school Monday.

The Department of Education says a caller tipped the department off before 17-year-old Hasan Simmons arrived at school. Police officers arrested the teen outside Monday morning. Authorities took Simmons into custody after they say they found a loaded 9 mm weapon on him.

Simmons faces an adult charge of criminal possession of a weapon and the DOE says it is in the process of suspending the teen.

Parents complain the school should have been locked down. Some students say the incident highlights the need for better security. "The school should immediately put in metal detectors. That [would] lower [the] chance of someone bringing in a weapon," student Ernesto Fernandez said.