(CNN) -- One student died and another was injured Monday in a shooting outside a high school in Arlington, Texas, police said.
Arlington police say they responded to Lamar High School just before 7 a.m. after reports of a shooting just outside the school building. Officers found a male student with an apparent gunshot wound; he was taken to a hospital but later died of his injuries, Arlington police said.
A female student was grazed by gunfire, police said.
The school day begins at 7:35 a.m., police spokesperson Tim Ciesco said, so not all students had arrived by the time the shooting happened.
The suspected shooter was taken into custody, police said.
"Because the suspect is a juvenile, the department is unable to release his name. He has been charged with one count of Capital Murder and is currently being held at the Tarrant County Juvenile Detention Center. Additional charges are pending the outcome of the ongoing investigation," police said in a news release Monday afternoon.
"The suspect never entered the school building and ran from the campus immediately after firing the shots. The motive for the shooting remains unclear," added the release.
Lamar High School went on lockdown after the shooting and students and staff were dismissed for the day, school district spokesperson Anita Foster said.
Arlington is a city between Dallas and Fort Worth with a population of just under 400,000.