Regin is a sophisticated malware and hacking toolkit used by United States' National Security Agency (NSA) and its British counterpart, the Government Communications Headquarters (GCHQ). It was first publicly revealed by Kaspersky Lab, Symantec, and The Intercept in November 2014. The malware targets specific users of Microsoft Windows-based computers and has been linked to the US intelligence gathering agency NSA and its British counterpart, the GCHQ. The Intercept provided samples of Regin for download including malware discovered at Belgian telecommunications provider, Belgacom. Kaspersky Lab says it first became aware of Regin in spring 2012, but that some of the earliest samples date from 2003. Among computers infected worldwide by Regin, 28 percent were in Russia, 24 percent in Saudi Arabia, 9 percent each in Mexico and Ireland, and 5 percent in each of India, Afghanistan, Iran, Belgium, Austria and Pakistan.