The top U.S. counterintelligence official is advising Americans traveling to Russia for soccer's World Cup beginning this week that they should not take electronic devices because they are likely to be hacked by criminals or the Russian government.

In a statement to Reuters on Tuesday, William Evanina, an FBI agent and the director of the U.S. National Counterintelligence and Security Center, warned World Cup travelers that even if they think they are insignificant, hackers could still target them.

"If you're planning on taking a mobile phone, laptop, PDA, or other electronic device with you — make no mistake — any data on those devices (especially your personally identifiable information) may be accessed by the Russian government or cybercriminals," he said.