Security guards used a metal detector to search Saginaw High School (search) students Friday morning, a day after a sophomore was shot in the chest, allegedly by another boy who had been in a juvenile detention center with him.

The victim remained in critical condition Friday, but surgeons determined that the bullet didn't hit any organs, police said.

"Nothing vital was struck. Hopefully he's going to be all right," police Sgt. Mark Lively said.

Students were asked to report a half-hour early on Friday to avoid lines at the main entrance, where a metal detector was installed Thursday afternoon. The school has grappled with several violent incidents in the past year.

The suspect was caught by a security officer in a nearby yard, and a handgun he allegedly threw away while running was found, school district spokesman Michael Manley said.

The boys, both 15, enrolled at Saginaw High just weeks ago after being released from the same juvenile detention center (search) and knew each other, authorities said.

"I didn't know what to think of it," said ninth-grader Lashunta Cole, 14, who was in math class when the shooting happened one floor above her. "It was crazy."

Since last December, shots were fired in the high school parking lot, a 17-year-old attempted to slash another student's throat in the hall, two teens attacked a police officer in the parking lot after a basketball game, and a drive-by shooter opened fire as hundreds of students were leaving the homecoming dance, injuring two.

Manley, a 33-year veteran of the school district, said disputes that begin on the streets, are carrying over into the schools.

"That's what makes this so difficult to get a handle on," he said. "There's so much violence in this community."

The metal detector will be permanent at the school, which also is considering other security measures, Manley said.

"This is a whole different level," he said. "This was the last straw."

Attendance appeared to be normal and no weapons were found Friday, he said.