WASHINGTON — Special Counsel Robert Mueller’s investigation into Russian election meddling ramped up Monday, with charges against President Donald Trump’s former campaign chairman and one of his associates. Separately, former Trump campaign adviser George Papadopoulos is pleading guilty to lying to the FBI about his contacts with Russians.

A look at what we know now:

WHO WAS INDICTED?

Trump’s former campaign chairman, Paul Manafort, and former Manafort business associate Rick Gates were indicted on felony charges and pleaded not guilty. Manafort was fired from the Trump campaign in August 2016 after word surfaced that he had orchestrated a covert lobbying operation on behalf of pro-Russian interests in Ukraine. Gates was a longtime associate of Manafort’s and worked for the Trump campaign past Manafort’s ouster. As of two weeks ago, Gates was still working for Tom Barrack, a Trump confidant, helping with the closeout of the inauguration committee’s campaign account.

WHAT ARE THEY ACCUSED OF?

The separate charges against Manafort and Rick Gates contend the men acted as unregistered foreign agents for Ukrainian interests. The indictments also include several other financial counts involving tens of millions of dollars routed through offshore accounts.

The indictment lays out 12 counts including conspiracy against the United States, conspiracy to launder money, acting as an unregistered foreign agent, making false statements and several charges related to failing to report foreign bank and financial accounts. The indictment alleges the men moved money through hidden bank accounts in Cyprus, St. Vincent and the Grenadines and the Seychelles.

The indictment accuses Manafort of using “his hidden overseas wealth to enjoy a lavish lifestyle in the United States, without paying taxes on that income.”

WHO IS GEORGE PAPADOPOULOS?

George Papadopoulos was a member of the campaign’s foreign policy team. He is pleading guilty to lying to federal agents about his dealings with several Russians who were offering “dirt” on Trump’s Democratic rival, Hillary Clinton.

Papadopoulos’ plea occurred on Oct. 5 and was unsealed Monday. In court papers, he admitted lying about the nature of his interactions with “foreign nationals” who he thought had close connections to senior Russian government officials.

Trump aides have said he played a limited role in the campaign and had no access to Trump.

WHAT DOES THIS HAVE TO DO WITH RUSSIAN MEDDLING?

The guilty plea by Papadopoulos marked the first criminal count that cites interactions between Trump campaign associates and Russian intermediaries during the campaign.

Manafort’s indictment doesn’t reference the Trump campaign or make any allegations about coordination between the Kremlin and the president’s aides to influence the outcome of the election in Trump’s favor. The indictment does allege a criminal conspiracy was continuing through February of this year, after Trump had taken office.

WHAT DOES TRUMP SAY?

The president quickly tweeted about the charges against Manafort, saying the alleged crimes were “years ago,” and insisting there was “NO COLLUSION” between his campaign and Russia.

As he has before, he pointed instead to his Democratic rival in the election, Hillary Clinton. He tweeted: “Why aren’t Crooked Hillary & the Dems the focus?????”