CNN  — 

Samuel Little, the California inmate who claims to be one of the most prolific serial killers in US history, has been linked to 60 deaths, a Texas prosecutor said Friday.

Ector County District Attorney Bobby Bland said investigators have confirmed Little is connected to deaths in 14 states.

Little claims to have killed people between 1970 and 2005 in 14 states from Florida to California. Authorities had previously confirmed he was linked to 34 killings.

Samuel Little has confessed to at least 90 killings.

Little, 79, is in a California state prison, according to corrections department spokeswoman Vicky Waters. He is serving life sentences for three murders.

He has been cooperating with investigators from different states and is in bad health, Bland said. In November, Little was charged in Ector County for a 1994 killing.

Little was indicted a week ago in Ohio, accused of killing two Cleveland women decades ago, according to a statement from the Cuyahoga County Prosecutor’s Office.

Prosecutor Michael O’Malley said Little has confessed to five killings in Ohio, including three in the Cleveland area. Cuyahoga County’s cold case unit was able to identify two of the three victims, O’Malley said.

Little is charged with four counts of aggravated murder and six counts of kidnapping in the deaths of 21-year-old Mary Jo Peyton in 1984 and 32-year-old Rose Evans in 1991, O’Malley said.

LIttle was indicted Friday in Hamilton County, Ohio, for two killings in the Cincinnati area in the 1980s.

Little has told investigators he killed more than 90 people across the United States, the FBI has said.

A map on the FBI’s website says Little told investigators he killed women in these states — Arizona, Arkansas, California, Georgia, Florida, Illinois, Louisiana, Maryland, Mississippi, Nevada, Ohio, South Carolina, Tennessee and Texas — but the killings have not been confirmed.

The FBI is hopeful that portraits of women drawn by Little will help authorities to identify them and solve some cold cases. According to the FBI, Little chose to kill marginalized and vulnerable women who were often involved in prostitution or suffered from drug addiction. Their bodies sometimes went unidentified and their deaths uninvestigated.

Gary Leon Ridgway, dubbed the Green River Killer, pleaded guilty in 2003 to killing 48 women and was later charged with a 49th murder. The 49 guilty pleas gave Ridgway more murder convictions — though not necessarily more slayings — than any other serial killer in US history. He reportedly confessed to 71 killings.