Washington (CNN) US investigators believe Russian hackers breached Qatar's state news agency and planted a fake news report that contributed to a crisis among the US' closest Gulf allies, according to US officials briefed on the investigation.

The FBI recently sent a team of investigators to Doha to help the Qatari government investigate the alleged hacking incident, Qatari and US government officials say.

Intelligence gathered by the US security agencies indicates that Russian hackers were behind the intrusion first reported by the Qatari government two weeks ago, US officials say. Qatar hosts one of the largest US military bases in the region.

The alleged involvement of Russian hackers intensifies concerns by US intelligence and law enforcement agencies that Russia continues to try some of the same cyber-hacking measures on US allies that intelligence agencies believe it used to meddle in the 2016 elections.

US officials say the Russian goal appears to be to cause rifts among the US and its allies. In recent months, suspected Russian cyber activities, including the use of fake news stories, have turned up amid elections in France, Germany and other countries.

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