From the article posted above.
Human remains found, Oklahoma white supremacist leader might be connected
Suspected in the disappearances is the Universal Aryan Brotherhood. Investigators have focused on a gang leader, three-time convicted murderer Mikell Patrick "Bulldog" Smith, sources said.
Witnesses told investigators Smith, now 57, owns the Logan County land where remains were first found, the sources said.
Smith murdered a Moore schoolteacher in 1985 and is now serving life in prison without the possibility of parole. He originally was given a death sentence for the shotgun slaying.
While in prison, he murdered two cellmates and stabbed a guard in the heart, his criminal record shows. He at one time was described as "the most dangerous inmate in the penitentiary."
Involved in the excavations have been agents from the Oklahoma State Bureau of Investigation.
The OSBI confirmed Friday it is assisting the sheriffs of Logan, Oklahoma and Pottawatomie counties in "a joint investigation involving several missing persons."
Among those missing are Smith's brother, Phillip Martin Smith. Also missing is David Anthony Orr, of Del City, who was charged last year with drug and weapon offenses.
Namus file Phillip Martin Smith
Missing Person / NamUs #MP74874