SAN ANTONIO -- FBI agents exhumed the remains Wednesday of a man buried in an Atascosa County ranch, near Kyote, dubbed as the "Killing Fields."

Agents discovered the remains Tuesday on property located off Highway 173.

After exhumation, the remains were taken to the Bexar County Medical Examiner's Office, where an autopsy will be performed.

It's not known how long the remains may have been buried.

The remains are not the first to be discovered on the ranch, known as a dumping ground for the Mexican Mafia prison gang.

In November 2004, agents found a skeleton in a shallow grave after receiving a tip from an informant.