German officials in the federal state North Rhine-Westphalia are warned that they may become victims to espionage during the 2018 World Cup that kicks off in Russian on June 14, Deutsche Welle reported.
They are advised to refrain from taking electronic devices to Russia to avoid incidents when "travelers' phones are taken away and returned without explanation," the media outlet wrote.
According to the security manual, specifically issued by Ministry of the Interior of the North Rhine-Westphalia ahead of the sporting competition, similar incidents have allegedly taken place in Russia and Turkey "in the past."
READ MORE: 'Leave Your Cellphones at Home,' US Counter-Intel Chief Warns World Cup Fans
Another reason behind these instructions are Fan IDs that allows foreigners to enter Russia without visas.
"Although visa-free travel to the Russian Federation is advertised, Fan ID has become a compensating measure," the document said.
Germany's manual has been released just as, William Evanina, the director of the US National Counterintelligence and Security Center, has advised his American colleagues planning to attend the sporting competition to leave their cellphones and other electronic devices at home. He said that this is precautious measure to make sure that they are not hacked and to avoid making them vulnerable to criminals.
According to Reuters, UK security agencies have issued similar warnings to British fans and members of the England football squad coming to Russia.