ROSEBURG, Oregon (AP) -- A young gunman critically injured a 16-year-old in a school shooting early Thursday then held the gun to his own head after police cornered him, authorities said. Police spokesman Sgt. Aaron Dunbar said the shooter appeared to be a student. He was arrested after the attack at Roseburg High School. The school went into lockdown after the shots were fired about 7:45 a.m., and administrators were preparing to send students home. The suspect was not immediately identified, and no motive for the shooting was disclosed. A nearby elementary school in Roseburg, a southwest Oregon town of about 21,000 residents, also was locked down as a precaution.