More than 1.3 million Android devices were part of a global botnet. Google, along with partners and Japan's National Police Agency, arrested the XCPE botnet, which involved more than 1.3 million set-top boxes and other Android devices in 200 countries. The malicious backdoor could have been pre-built into the equipment's firmware by the Chinese manufacturer Videostrong Technology. Infected devices were used to create proxy networks and redirect malicious traffic. That is, an ordinary TV set-top box can, without the owner noticing it, become part of the attackers' infrastructure. Google stopped cooperation with the manufacturer.