A 14-year-old freshman girl shot and injured another female student and then killed herself inside a Texas high school bathroom on Thursday morning, Brewster County Sheriff Ronny Dodson said.

Dodson said the injured student ran outside seeking help and was taken to a hospital with injuries that weren't considered life threatening.

A police officer was accidentally shot in the leg by a marshal responding to the episode, Dodson said.

Five shots were fired during the incident at Alpine High School, leading to the lockdown of all district schools. A woman who answered the phone at the Alpine Independent School District described the situation as "contained."

None of those shot were immediately identified.

"I am currently monitoring the active shooter situation in Alpine," Texas Attorney General Ken Paxton said in a statement. "I have directed my office to offer any measure of support needed to assist the law enforcement officials currently working this case. I wish to extend prayers and sympathy to any victims' families and their loved ones who have been affected by this senseless act of violence."

Brewster County is in southwestern Texas near the Mexican border.

Alpine is a small public high school. It reported 277 students were enrolled at the school last year.

Fox News' Casey Stegall and The Associated Press contributed to this report.