GCHQ fears hackers will loot Government websites More local authorities, with less sophisticated security operations, are collecting council tax online. Hackers may shift their focus away from banks and retailers such as Amazon to hit Government services. Criminal hackers use viruses to take set up networks of remotely controlled PCs - known as botnets - in order to carry out frauds. In a recent exercise, GCHQ monitored a single botnet operated by hackers in Ukraine. It harvested more than 1,600 log-ins for Government services issued to members of the public in just 11 hours, who believed they were using a secure connection. In another fraud, internet criminals launched a sophisticated "phishing" attack against small businesses that were filing their tax returns at the HMRC website. They took advantage of the high volume of transactions in the days leading up to the deadline to avoid detection and fraudulently collect the businesses" rebate. "The Government ends up being the biggest free bank in the world, if we're not careful," Dr Levy warned. Hackers are now acting like major businesses with "dashboards" monitoring the success rate of different operations in real-time. There is a substantial online market place where specialist hackers remotely trade coding, server space and customers" passwords in order to pull off sophisticated hacks, Dr Levy said. The agency fears that Government websites could be compromised because people are using the same passwords for all their online accounts. Customers could use an internet shopping portal that has been compromised by hackers, before using the same passwords and email addresses to file their tax returns or claim benefits. Such users are a "nightmare" for the service, Dr Levy said.