UPDATE | Doctor: Most seriously hurt in LA shooting 'extremely lucky'

LOS ANGELES (AP) — Four students were shot and wounded, one critically, inside a Los Angeles middle-school classroom this morning, and police arrested a female student believed to be 12 years old, authorities said.

A 15-year-old boy hit in the head was transported to a trauma center in critical but stable condition, according to fire department spokesman Erik Scott. A 15-year-old girl with a gunshot wound to the wrist was taken to a hospital in fair condition, Scott said. Two more children were grazed by bullets.

Police arrested the female student and recovered a gun after the shooting that happened just before 9 a.m. at Salvador B. Castro Middle School, west of the city's downtown. Preliminary information indicated she was 12, said Steve Zipperman, chief of the Los Angeles Unified School District police force.

Authorities did not immediately identify a possible motive, saying the investigation was in its early stages.

The most seriously injured victim was brought to Los Angeles County-USC Medical Center and remained in intensive care during the afternoon but was doing well.

"This child was extremely lucky," said Dr. Aaron Strumwasser, a trauma surgeon. "The trajectory of the bullet did not hit any vital structures that were an immediate threat to life."

Dr. Carl Richard Chudnofsky, chief of emergency medicine, said the teen's prognosis was good.

The girl wounded in the wrist also remained hospitalized but was described as resting comfortably.

Three other victims, including a woman, were initially described as having suffered abrasions. But the two children actually had grazing gunshot wounds, Strumwasser said. They were treated and released.

The woman was not brought to the hospital.

Television news footage showed a girl with dark hair wearing a sweatshirt being led out of the school in handcuffs a short time after the shooting while police cars blocked an intersection near the school and parents gathered at the street corner, talking on their phones and awaiting word about their children.

1:10 p.m.

LOS ANGELES (AP) — Two students were shot inside a Los Angeles middle school classroom this morning and police arrested a female student suspect, authorities said.

A 15-year-old boy who was shot was transported to a trauma center in critical condition, according to the Los Angeles Fire Department. A 15-year-old girl with a gunshot wound was taken to a hospital in fair condition, a department statement said.

A 30-year-old woman who was not shot suffered unspecified minor injuries, the statement said.

The gunfire erupted shortly before 9 a.m. at Salvador B. Castro Middle School just west of the city's downtown, police said.

Television news footage showed a girl with dark hair and wearing a sweatshirt being led out of the school in handcuffs a short time later.

"With the suspect in custody the situation is under control," said Sgt. Edward Bernal of the Los Angeles Unified School District Police Department.

A gun was recovered, Bernal told KTLA-TV.