65-year-old man pleads not guilty in 1978 and 1994 slayings

A white-haired ex-convict from Mississippi whom police call a serial killer pleaded not guilty Wednesday to murder and sex assault charges in the cold case slayings of three women.

Nathaniel Burkett, 65, remained in a wheelchair during his brief appearance before a judge who took his plea and set Burkett's next appearance for Jan. 7. A state court judge is expected at that time to set a trial date.

Burkett is accused of killing 22-year-old Barbara Ann Cox in April 1978 and 27-year-old Tina Gayle Mitchell and 32-year-old Althea Maria Williams in separate slayings in 1994. Police say each woman was sexually assaulted, strangled and left dead in a neighborhood near where Burkett lived at the time.

Burkett has two previous manslaughter convictions, including one in Mississippi that put him in prison from 1983 to 1992 in the death of his mother.

He was in Nevada prisons from 2004 to 2009 on a manslaughter conviction in the September 2002 strangulation of a 41-year-old woman in Las Vegas.

Burkett was living with his sister in Mississippi before his arrest and extradition in August to Las Vegas.