Britain's National Infrastructure Security Co-ordination Centre (NISCC), set up to investigate information technology crime, had urged businesses to stay alert.
"We have never seen anything like this in terms of the industrial scale of this series of attacks," NISCC-director Roger Cumming told the Financial Times.
"This is not a few hackers sitting in their bedrooms trying to steal bank account details from individuals. This is aimed at organisations, targeted at gaining information and is extremely well-organised and well-structured," Cumming added.
The attackers’ specific countries of origin have not been revealed. However, there is currently an investigation underway from the NISCC and National Hi-Tech Crime Unit to shutdown the Internet addresses the attacks are coming from.