As a group of boys at a Utah high school changed Tuesday morning into gym clothes for physical education class, a straight-A student pulled out a knife in the locker room and stabbed five of his classmates, sending the injured running for their lives and covered in blood, police said.

The 16-year-old suspect with no record of disciplinary trouble also stabbed himself in the neck and was cornered by school workers until a police officer assigned to Mountain View High School got to the locker room and subdued him with a Taser shot.

The five victims are all expected to survive, hospital officials said Tuesday afternoon. The two most seriously injured were in critical but stable condition, according to Utah Valley Hospital.

The suspect was treated and released following the attack that spread fear and panic among students who described a gruesome scene immediately after the stabbings.