Associated Press

OKLAHOMA CITY -- An Oklahoma state agency's investigation into a series of truck stop slayings has led to an FBI initiative aimed at solving serial killings where the bodies have been dumped along U.S. highways.

A convicted killer was indicted in Texas earlier this week on a charge of capital murder in the death of a woman last seen alive at a truck stop in western Oklahoma.

John Robert Williams, who was sentenced to life in prison after pleading guilty to an unrelated killing, now faces charges in two deaths believed to be linked.

The FBI is now investigating such deaths with the Highway Serial Killings initiative, which was created after the federal agency collaborated with the Oklahoma State Bureau of Investigation as it looked into truck stop deaths.