Nigel Cawthorne.com

Murders and serial killers don’t always get caught. For each newsworthy conviction there are many others cases where violent and disturbed individuals still lurk among us. In the USA alone it is estimated that may be up to 500 murderers on the loose. Some will certainly go on to become serial killers. The cases covering in the alarming overview, the biggest of its kind, include:

‘The Zodiac Killer’, terror of the San Francisco Bay Area, who left encrypted message after each murder.Argentina’s crazed highway killer, who has mutilated and killed at least  five people since 1997, dumping their bodies along remote highways.‘The Twin Cities Killer’, responsible for a series of over 30 murders in the street of Minneapolis and St. Paul, whose victims are mostly prostitutes.Costa Rica’s elusive ‘El Psicópata’ (The Pyschopath), thought to have murdered at least 19 people in this small quiet Central American country. ‘The Monster of Florence’, responsible for a series of 15 sexual slayings outside Florence, where all the victims were courting couples.