'Night Stalker' Richard Ramirez, convicted mass murderer, dies

(CNN) -- Richard Ramirez, a mass murderer and serial rapist known as the "Night Stalker" for his 1984-85 crime spree in California, died Friday morning of natural causes at age 53, the California Department of Corrections and Rehabilitation said.

The California death row inmate died at Marin General Hospital north of San Francisco, the department said.

Ramirez was convicted in 1989 of 13 murders -- 11 in Southern California and two others in the San Francisco area -- along with five attempted murders, 11 sexual assaults and 14 burglaries.

Ramirez, a professed "satanist," was dubbed the "Night Stalker" for his preference of breaking into houses in the wee hours of the morning.

His attacks, many of them on elderly couples, terrified Southern California. His preferred method of attack was to quickly kill the male and rape -- sometimes repeatedly -- the female after ransacking the home for valuables. Some of his victims survived and provided descriptions, but police were unable to name a suspect.

Arrested in 1985, Ramirez was sentenced to die after his conviction in 1989.

Ramirez is the 59th inmate condemned in California to have died of natural causes since the state reinstated capital punishment in 1978, the department of corrections said. Twenty-two others committed suicide, and six died of other causes.

The state, which has 735 offenders on death row, has executed 13 inmates since 1979; one other California offender was executed in Missouri, the department said.

CNN's Deanna Hackney, Greg Morrison and Jason Hanna contributed to this report.