The head of Honduras National Autonomous University says a police officer has turned himself in to face charges that he killed her son in a case that set off a campaign to clean up a corruption-plagued force.

Julieta Castellanos tells The Associated Press that she hired a private investigator to find the suspect. She said Friday that she gave the information to authorities, and the officer surrendered to Honduras' human rights commission after police started looking for him.

Castellanos' son was slain with a friend a year ago and their killings sparked a movement against police corruption and impunity in the Central American nation.

The motive in the crime remains a mystery, but prosecutors say some police officers kidnapped and killed the two young men. Two suspects remain at large.