A south Oklahoma City high school is on lockdown after a student was caught carrying a gun on campus.

U.S. Grant High School Superintendent Karl Springer says in a letter posted on the district's Web site the school was placed on lockdown Tuesday after the student was taken into custody Monday.

Doors to the school and to classrooms are locked and hallway access is being restricted.

The lockdown is to continue until students are released at the end of classes Tuesday.