Hackers threaten seven major South Korean banks of a cyber attack, ask for ransom

A hacker group has threatened a cyber attack against seven major South Korean banks if they do not pay 360 million won ($315,000) in the virtual currency bitcoin.

The group, called Armada Collective, has threatened to carry out a distributed denial-of-service ( **DDoS** ) attack if the demanded money is not paid by June 26, South Korean news agency Yonhap reported on Thursday. Among those affected are the country’s three largest banks - KB Kookmin Bank, Shinhan Bank and Woori Bank - and others, such as KEB Hana and NH Bank, according to South Korea’s financial authorities. The banks have boosted their security systems in the face of a possible attack that could disrupt their websites. DDoS is a common cyberattack tactic that involves trying to overwhelm a website or service with a large volume of traffic from diverse sources, reports Efe News. The Armada Collective has also threatened other companies in the past with such attacks, demanding payments in the Bitcoin **cryptocurrency** . In November 2015, several secure email services were targeted by the group, which has also made cyber attack threats in countries including Switzerland and Thailand.