Four people were hurt in a shooting at Timberview High School in Arlington, Texas, Wednesday morning, authorities said.
The suspect, an 18-year-old student, fled the scene and was taken into custody hours later, authorities said.
Two of the victims suffered gunshot wounds, police said. Three victims were students and one was an older person who may have been a teacher, police said.
Three of the four victims were hospitalized: a 15-year-old boy with gunshot wounds in critical condition, a 25-year-old man with gunshot wounds in good condition and a teenage girl with abrasions who has since been released, police said.
A family member confirmed to ABC News that one of the victims was Calvin Pettitt, who appears to be an English teacher at the school.
Police identified the suspect as 18-year-old Timothy George Simpkins. After announcing a search for him, police said he was taken into custody and charged with three counts of aggravated assault with a deadly weapon. The teen suspect communicated with his attorney before turning himself in without incident shortly before 1:15 p.m. and has been booked into the Arlington City Jail, police said. His bond has been set at $75,000.
Police said this was not a random act of violence and that the suspect allegedly got into a fight before drawing a weapon. The shooting occurred around 9:15 a.m. in a classroom on the second floor of the school, police said.
A teacher told ABC News he heard the shooting and barricaded in a classroom with his students.
The "all clear" was given at the school following a lockdown. Students are being escorted to another building to be reunited with their families, the Mansfield Independent School District said.
ATF officials were at the scene in Arlington, located between Fort Worth and Dallas.
Texas Gov. Greg Abbott said in a statement: "Our hearts go out to the victims of this senseless act of violence."
"Thank you to the law enforcement officers and first responders who arrived on the scene to help the victims and prevent further violence," he said. "I have spoken with the Mayor of Arlington and offered any assistance the state can provide, and I have directed the Texas Department of Public Safety to make state resources available to help bring the criminal to justice."