JEFFERSON CITY, Mo. (AP) — A former Missouri high school teacher has been sentenced to 10 years in federal prison for distributing child pornography.

U.S. Attorney Tammy Dickinson says 26-year-old Stephen Gregory Strobel of Jefferson City was sentenced Wednesday after pleading guilty April 18 to the charge.

Prosecutors say a woman in Wooster, Ohio, discovered in April 2014 that her 13-year-old daughter had engaged in a sexually explicit Internet chat with Strobel. Investigators contacted Strobel a month later at St. Elizabeth High School in the tiny village of St. Elizabeth southwest of Jefferson City.

Strobel admitted exchanging pornographic photos with girl and sending a video from the girl to another person. He also admitted trading photos of other underage girls with various people online but said he never asked the ages of the depicted children.