Investigators believe they have connected "Grim Sleeper" suspect Lonnie Franklin Jr. to 10 murders.
Now they are trying to tie him to dozens more.
More than 30 cold case files dating back to 1984 are getting a new look in light of Franklin's arrest, Los Angeles Police Chief Charlie Beck said Friday.
"Now that we know who he is, where he lives, the cars he drove, have people to interview, we will go over all those old cases and look for connections," Beck said.
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Investigators will upload Franklin's DNA profile into a national database to see if it matches other samples where the DNA had degraded and scientists only were able to get a partial sample, Beck said.
Franklin was dubbed the Grim Sleeper after a string of murders of young black women had south Los Angeles on edge in the mid-1980s. Then the killings suddenly stopped, only to resume again 14 years later.
Now, investigators say they have possibly uncovered the reason for the long respite: He may have been spooked by a near miss by police in 1988.
Franklin was arrested Wednesday on 10 counts of murder and other charges at his lime-green house, just three doors down from a home that was searched extensively by police 22 years ago after the killer's only known survivor led cops there.
Beck also noted that billboards plastered with a $500,000 reward and the suspect's police sketch were posted just eight blocks from Franklin's house and he drove by them every day.
"Either he became more careful or he stopped his behavior for a number of years. That's an evolving theory," Beck said. "It's going to be difficult to be absolutely certain absent his confession."
Franklin was arrested at least 15 times for car theft, burglary, assaults and other crimes, but avoided prison despite calls by law enforcement officials for tough sentences, according to Los Angeles County court records released Friday and obtained by the Los Angeles Times.
Franklin faced up to three years in prison in 2003 after pleading no contest to receiving stolen property, He was sentenced to 270 days in jail and released in May 2003, more than four months early, the records showed. Two months later, the body of one of Franklin's alleged victims was found.
Franklin's public defender, Regina Laughney, said she was still reviewing materials in the case and it was too early for her to comment.
Law enforcement said despite more than two decades of old-fashioned police work, they were finally able to crack the case using a new and disputed technique of "familial DNA."
In early June, the state Department of Justice ran newly submitted DNA through a database of 1.5 million samples.
The database found no identical matches, but did find a "familial" match to a convicted felon whose DNA indicated he was either a brother or the son of the killer. An earlier search in 2008 had found no familial matches, but Franklin's son was added to the database in recent months for a felony weapons conviction.
State investigators alerted the LAPD of Franklin's identity on June 30 after verifying the match through birth certificates and other records.
But police still needed a sample of Franklin's DNA to definitively match it to what was found on the victims.
An undercover officer pretending to be a waiter in Los Angeles collected tableware, napkins, glasses and pizza crust at a restaurant where the suspect ate, allowing detectives to obtain a DNA match.
Franklin made a first court appearance Thursday on the murder counts as well as one count of attempted murder and special-circumstance allegations of multiple murder that could lead to the death penalty or life in prison without possibility of parole.
His arraignment was postponed until Aug. 9 at the request of his attorney.
Associated Press Writer Thomas Watkins contributed to this report.