A global cyberattack targetted more than 100 banks in 30 countries stealing hundreds of millions of dollars, The New York Times reported Saturday, citing a report from computer security company Kaspersky. The newspaper said the attack involved malicious software that gave hackers access to banking systems. It identified a group of Russians, Chinese and Europeans hackers that transfered around $300 million stolen from bank accounts to their own accounts around the world.

The gang used emails to trick pre-selected employees into opening malicious software files, a common technique known as spear phishing. They were then able to get into the internal network and track down administrators' computers for video surveillance.

In this way, Kaspersky said, the criminals learned how the bank clerks worked and could mimic their activity when transferring the money.

Hackers largely focused on banks in Russia, but millions of dollars were also taken from banks in Japan, the Netherlands, Switzerland and the United States as well, the Times said.