Q&A-What we know about U.S. probes of Russian meddling in 2016 election

By Amanda Becker

June 14 (Reuters) - U.S. intelligence agencies have alleged that Russia interfered in the 2016 presidential election to benefit President Donald Trump.

Law enforcement agencies and congressional committees are investigating Russian meddling and possible collusion with members of Trump's campaign. Here is what is publicly known and not known:

How did the investigations begin?

Former President Barack Obama ordered U.S. intelligence agencies to assess whether Russia tried to intervene in the election after a cyber attack on the Democratic National Committee in July 2016 and the publication of thousands of hacked personal emails from Hillary Clinton's campaign manager in the month before the Nov. 8 election. Obama told intelligence officials to deliver a report on possible foreign interference before he left the White House in January 2017.

What did the intelligence agencies find?

The Central Intelligence Agency, the Federal Bureau of Investigation and the National Security Agency concluded in a report declassified in January that Russian President Vladimir Putin ordered a campaign not just to undermine confidence in the U.S. electoral system but to affect the outcome.

The agencies said Putin and the Russian government had a clear preference for Trump to win the White House. Putin's associates hacked information, paid social media "trolls" and backed efforts by Russian government agencies and state-funded media to sway public opinion, the agencies said.

The report stopped short of assessing whether Russia succeeded in swaying the election result.

Putin and other Russian officials have repeatedly denied interfering in the U.S. election.

How many U.S. investigations are there into Russian election meddling?

Comey told the House Intelligence Committee on March 20 that the FBI was investigating Moscow's role in the election, including possible collusion with Trump's campaign.

The Justice Department announced on May 17 that it had appointed Robert Mueller, a former FBI director, as special counsel to lead an independent Russia probe. Mueller would, if the evidence merits, work in tandem with the FBI to handle any related criminal prosecutions.

In addition, there are multiple committees in the Senate and House of Representatives investigating various aspects of Russian election meddling.

What has Trump said about Russia's role in the election?

He has not taken a clear public position.

At a July 2016 news conference, Trump addressed an FBI probe into Clinton's use of a private email system when she was secretary of state and emails that had possibly been deleted by saying: "I will tell you this, Russia: if you're listening, I hope you're able to find the 30,000 emails that are missing."