Rajendrasinh Babubaha Makwana, a former computer engineer at mortgage broker Fannie Mae has been indicted in the US for allegedly placing a virus into its systems which would have closed down 4,000 servers, disabling most of its data center IT.

A statement made to the court by an FBI agent said the virus had been planted on October 24th last year. It said: "A senior computer engineer discovered the virus on October 29. The malicious code was hidden after a blank page, and "it was only by chance" that the senior engineer scrolled down and found the virus. The engineer locked down Fannie Mae's servers to determine whether other viruses were hidden inside and where the virus had come from"

Makwana was arrested after an IP address linked to laptop was discovered as the source of the virus, the statement said. The virus was timed to activate on January 31st.