Sensitive data is believed to be sent back to the Kremlin, run by Russian president Putin

Intelligence services have been warned that Russia is using diplomatic cover in European countries to bring smuggle in spying and transmission equipment.

The technology is thought to be concealed in the boots of vehicles which the Russian government purchased for diplomats and staff who operate out of European embassies.

The GRU, Russia’s military intelligence agency, is suspected of using the equipment to send and receive encrypted data to field agents who are operating under diplomatic cover or have entered the EU as migrants.

The existence of the devices, which are concealed in the tyre wells of adapted cars, was first discovered in 2017 by intelligence services in eastern Europe, where surveillance teams began monitoring Russian agents driving diplomatic vehicles to remote locations, apparently to access