Thanks to newly available DNA technology, Los Angeles police have charged John Floyd Thomas, 72, in two cold-case murders from the 1970s, The Times of London reports. Police say that Thomas's DNA has allegedly been traced to at least five other murder scenes in two different sets of sex killings previously thought unrelated. In the first wave of killings, the so-called "Westside Rapist" killed 17 women, but stopped in 1978, the year Thomas went to jail for raping a woman in Pasadena. The second wave began after Thomas' release in 1983 and claimed the lives of five more women. Clocking in at upwards of 25 murders, the two alleged crime waves would represent Los Angeles' worst crime. An additional 20 women survived attacks, but in the absence of DNA evidence, police didn't link the two crime waves since witnesses gave conflicting descriptions of the assailant to the police.