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Investigators in the United States believe Russian hackers breached Qatar's state news agency and planted a fake news report that contributed to the latest crisis among Gulf states, CNN reported on Tuesday, citing U.S. 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, said Qatari and U.S. government officials.

Intelligence gathered by U.S. security agencies indicates that Russian hackers were behind the intrusion first reported by the Qatari government two weeks ago, officials said.

The fake news report in question involves comments attributed to Qatari Emir Sheikh Tamim bin Hamad Al Thani, in which he allegedly described Iran as an "Islamic power" and criticized U.S. President Donald Trump's policy towards Tehran.

The comments appeared in the official Qatar News Agency. Qatar immediately dismissed them and said the website of its news agency was hacked.

After the comments were published, however, several Arab countries blocked the website of the Qatari-owned Al-Jazeera television network.

On Monday, Saudi Arabia, Egypt, Bahrain and the United Arab Emirates all cut diplomatic ties with Qatar and shut down land, sea and air links. Jordan and Mauritania followed suit on Tuesday.

It is not yet clear whether the U.S. has tracked the hackers in the Qatar incident to Russian criminal organizations or to the Russian security services blamed for hacks involving the last U.S. presidential election, according to CNN.

One official noted that based on past intelligence, "not much happens in that country without the blessing of the government."

The FBI and CIA declined to comment. A spokeswoman for the Qatari embassy in Washington said the investigation is ongoing and its results would be released publicly soon.

Qatari Foreign Minister Sheikh Mohammed Bin Abdulrahman al-Thani told CNN on Tuesday the FBI has confirmed the hack and the planting of fake news.

"Whatever has been thrown as an accusation is all based on misinformation and we think that the entire crisis being based on misinformation. Because it was started based on fabricated news, being wedged and being inserted in our national news agency which was hacked and proved by the FBI," he said.