Police were able to identify the culprits thanks to CCTV and placed the gang under surveillance during the last four months.
The leader of the gang is a 45-year-old Italian, a “pioneer” of a technique using explosives, according to hoy.es. The method reportedly used just enough explosive so that cashpoints could be opened without the banknotes being destroyed.
The man is said to have imported the cash machine-busting method from Italy and to have trained his fellow perpetrators.
According to security sources cited in hoy,es, the gang were responsible for more than half a dozen bank robberies in the last few months.
According to the same source, the men are aged between 32 and 59 and of Italian, Dutch and Colombian nationality.
The latest police bust follows a similar arrest of a gang in March this year who used gas to blow up ATMs in the same region.