A high school teacher in the US is in custody after firing a shot inside a classroom.
Around 11:30am on Wednesday (US time) police were called to Dalton High School in Dalton, Georgia, about 145km north of Atlanta.
There they found a teacher had barricaded himself in a classroom.
Witnesses told police the incident began when the teacher refused to let some students into his classroom. They alerted the principal, who tried to get in using a key but couldn't after the teacher forced it shut, reported local paper the Atlanta Journal-Constitution.
That's when a shot was heard, sending students into a panic.
"We had officers inside the building quickly," police spokesman Bruce Frazier said.
After about half an hour, they had the suspect in custody.
No students were hurt in the incident, except a girl who injured an ankle fleeing the scene.
Police said the teacher, armed with a handgun, didn't want to involve students in whatever it was he was doing.
The incident happened on the day students at Marjory Stoneman Douglas returned to school, after 17 of their classmates and teachers were shot dead.
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