A military judge has sentenced an Air Force instructor to four years in prison for raping a female trainee at the South Texas base where he worked.

Lt. Col. Matthew Van Dalen also sentenced Staff Sgt. Eddy Soto to a dishonorable discharge after convicting him of rape Saturday during a military trial at Joint Base San Antonio-Lackland.

More than 30 Lackland instructors have been investigated in the military sex scandal. Soto was the ninth trainer convicted in the scandal and sentenced to prison or hard labor.

Van Dalen acquitted Soto on charges of aggravated sexual assault and wrongful sexual contact.

Soto previously pleaded guilty to five counts, including having had sex with a female trainee and with the wife of a male trainee.