The Associated Press reports that a serial killer has pleaded guilty to the 1994 murder of a Texas woman. In Dallas, the 78-year-old prisoner claimed to have killed 90 people as he traveled the country for decades. Samuel Little entered a guilty plea to murder charges today in the 1994 strangulation murder of a Texas woman.

Denise Christie Brothers was found in a vacant lot a month after she was reported missing. Little has received another life sentence for the murder of Brothers.

In 2014, Little was convicted of killing three women in the Los Angeles area in the 1980s. He was sentenced to life sentences for those killings, and shortly after he confessed to dozens more murders in 20 states since 1970.

After his confessions, investigators from Florida to California began looking over old murder cases and they have concluded he is responsible for at least 40 unsolved cases. In the most recent of these cases, he was linked to the Tennessee death of Martha Cunningham, who was found murdered in 1975 in Knoxville. She was nude from the waist down when her body was discovered in a wooded area.

Little is now among the most deadly serial killers in American history.

*Photo credit The Associated Press