(CNN) -- The San Francisco Police Department is reopening a 25-year-old homicide that may be linked to convicted killer Richard Ramirez, known during his 1984-85 spree as the "Night Stalker."
Detectives recently obtained a warrant to test Ramirez's DNA based on new leads in the 1984 death of 9-year-old Mei Leung, who was sexually assaulted and killed in the basement of her home in the city's Tenderloin district, police said.
"There are no charges at this time," explained David Shinn, deputy director of the Bureau of Investigation. Inspectors went to San Quentin Prison, where Ramirez is awaiting execution, to get the DNA sample.
Ramirez was convicted in 1985 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 brutal string of 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.
After an attack in San Francisco in August 1985, however, police finally got a break. A Tenderloin hotel manager recognized the descriptions as a man who had stayed at the hotel periodically for a year and a half.
Ramirez had already left San Francisco, however, and attacked again in Los Angeles on August 24. A week later, Ramirez took a bus from Tucson, Arizona, where he'd been visiting his brother, and was recognized from his picture, now gracing the cover of newspapers, at a store near the downtown Los Angeles bus station.
He fled and was finally brought down by residents of an east Los Angeles neighborhood who recognized him as he tried to steal two cars. They held him down until police arrived.
Mei Leung's death was an open case for 25 years until what police described as new information pointed to Ramirez as a possible suspect. One of the investigators, Inspector Holly Pera, was just starting with the department when the girl was slain.
"It is the type of case as a new officer that you don't forget," Pera said. She and her partner, Inspector Joseph Toomey, have had the case for a couple of years.
Police said the family of the dead girl were notified of the developments and were described as being grateful that the crime is still being investigated.
Ramirez, sentenced to die in 1989, later married a woman who wrote him some 75 letters after his capture.