President Donald Trump. Chris Kleponis/Pool - Getty Images This month's revelations about the investigation into Russia's election interference and President Donald Trump's campaign's ties to Moscow have come at a dizzying pace.

We learned that Robert Mueller, the special counsel leading the FBI's investigation, obtained a search warrant to examine Facebook accounts linked to Russia after the company announced that the "inauthentic" users had purchased more than $100,000 in ads during the election.

We also learned more details about the FBI's longtime interest in Trump's campaign chairman, Paul Manafort — and his overtures to a Russian oligarch last July.

The president's legal team, meanwhile, is clashing over how cooperative to be with Mueller, who is homing in on key White House players as he examines whether Trump sought to obstruct justice when he fired James Comey as FBI director.

Here is a look back at some of the month's most important developments: