CLAREMORE, Oklahoma - The Rogers County Sheriff's Office said it has intercepted an inmate's letter that contains a death threat to the President of the United States.

The U.S. Secret Service has been notified and is conducting an investigation.

At this time, officials say they can't release the contents of the letter, but they confirmed the letter was written by inmate Hunter Hines, 18.

Hines was arrested in May after he ran away with a 12-year-old girl.

To search for the pair, Rogers County deputies spread out on the ground and sheriff Scott Walton flew with our SkyNews 6 crew to look for possible hiding places. Our pilot spotted an abandoned camper, and deputies found one of the girl's shoes nearby.

The girl and Hines were recovered on May 8.

Hines initially was arrested for harboring a runaway, which is a misdemeanor, and jailed on a $50,000 bond. Shortly after, charges of rape, molestation, sodomy, contributing to the delinquency of a minor and breaking and entering were added.