On May 17, 2017, Deputy Attorney General Rod Rosenstein appointed Robert Mueller as special counsel to lead the investigation into Russian interference in the 2016 U.S. presidential election. The action came eight days after President Donald Trump fired FBI Director James Comey. Trump acknowledged later that the FBI’s Russia investigation, which looked into possible collusion by the Trump campaign and which the president called “a made-up story," figured in his decision.

Here are some key event in the probe, which concluded last month. A redacted version of Mueller’s report is being released Thursday.

2017

May 17: Deputy Attorney General Rod Rosenstein appoints former FBI director Robert Mueller as special counsel to lead the Russia probe.

June 14: The investigation is expanded to include possible obstruction of justice by Trump.

Oct. 30: Paul Manafort and his business partner Rick Gates are indicted on charges that include conspiracy against the United States and money laundering. Trump’s former campaign adviser, George Papadopoulos, pleads guilty to lying to the FBI about his contacts with Russian officials.

Dec. 1: Former national security adviser Michael Flynn pleads guilty to lying to the FBI about his conversations with Russian Ambassador Sergey Kislyak.

2018

Feb. 16: A federal grand jury indicts 13 Russians and three Russian entities on charges of conspiring to defraud the United States and interfere with the 2016 presidential election. Richard Pinedo, a previously unknown computer expert, pleads guilty to selling bank account numbers to Russians involved in election interference.

Feb. 20: Alex van der Zwaan, a Dutch lawyer working for a New York City law firm, pleads guilty to lying to the FBI about his interactions with Gates and a “Person A” related to a report his law firm had prepared on the trial of a Ukrainian politician. van der Zwaan later served 30 days in prison and was deported.

Feb. 22: A new indictment charges Manafort and Gates with 32 financial charges, including money laundering and bank fraud.

Feb. 23: Gates pleads guilty to charges of conspiracy and lying to investigators outlined in a superseding criminal information filed by Mueller. Manafort is charged in a superseding indictment with secretly paying European politicians to lobby on behalf of Ukraine.

April 9: FBI agents raid the home, hotel room, and office of Trump’s personal attorney Michael Cohen.

June 8: A new superseding indictment charges Manafort and Konstantin Kilimnik, a former Manafort aide with suspected ties to Russian intelligence, with conspiracy and obstruction of justice in an alleged attempt to influence the testimony of others. Manafort also is charged with conspiracy to launder money and acting as an unregistered foreign agent.

July 13: A federal grand jury indicts 12 Russian military intelligence officers on charges of hacking and releasing Democratic emails during the 2016 campaign.

Aug. 21: A federal jury in Virginia convicts Manafort on eight counts of fraud. Cohen pleads guilty in federal court in Manhattan to eight counts related to tax fraud and campaign finance violations

Sept. 7: A judge sentences Papadopoulos to 14 days in prison for lying to the FBI.

Sept. 14: Manafort pleads guilty to two counts of conspiracy and enters a “cooperation agreement” with prosecutors.

Nov. 8: Attorney General Jeff Sessions, whose decision to recuse himself from the Russian probe angered Trump, resigns at the president’s request. Matthew Whitaker, Session’s chief of staff and public critic of the Russia probe, is appointed acting attorney general by Trump.

Nov. 20: Trump’s lawyers say they’ve submitted written answers to questions from Mueller’s team.

» READ MORE: Inside Trump’s refusal to testify in the Mueller probe

Nov. 26: Mueller files court papers alleging Manafort breached his plea agreement by lying and arguing any deal on prison time was now moot.

Nov. 29: Cohen pleads guilty to lying to Congress about the details of work on plans to build a Trump Tower in Moscow. “Individual 1," a person believed to be Trump, makes an appearance in court documents.

Dec. 4: Mueller’s team recommends no prison time for Flynn, citing his “substantial assistance” and cooperation in the Russia investigation.

Dec. 12: A judge sentences Cohen to three years in prison on charges related to campaign finance violations, tax evasion and lying to Congress. In his guilty plea, Cohen says then-candidate Trump directed him in 2016 to pay hush money to two women who alleged affairs with the real-estate developer.

2019

Jan. 25: FBI agents arrest longtime Trump associate Roger Stone after a grand jury indicts him on charges of lying to investigators about communications with the Trump campaign about hacked emails possessed by WikiLeaks,

Feb. 22: U.S. District Court Judge Amy Berman Jackson imposes a gag order in Stone’s case after he posts an Instagram photo of her with a crosshair symbol near her head.

Feb. 23: Mueller, in a more-than-800-page sentencing memorandum, calls Manafort a “hardened” criminal who “repeatedly and brazenly” broke the law for over a decade, even after being indicted.

March 7: Manafort is sentenced to nearly 4 years in prison for financial crimes, including bank fraud, tax fraud, and concealing a foreign bank account. The term is considerably less than the 19 to 24 years prosecutors had sought.

March 13: Manafort is sentenced for his guilty plea to conspiracy against the United States and conspiracy to obstruct justice. Since parts of both sentences will be served concurrently, , Manafort will spend about 7 ½ years behind bars for both convictions, including about 9 months already served.

March 22: Mueller ends the investigation, sending report numbering hundreds of pages to newly appointed Attorney General William Barr.

March 24: Barr sends a four-page summary to Congress. It says the investigation "did not establish that members of the Trump campaign conspired or coordinated with the Russian government in its election interference activities.” As to possible obstruction of justice, it says that while the report “does not conclude that the President committed a crime, it also does not exonerate him.” Barr said he and Rosenstein had determined there was insufficient evidence "to establish that the President committed an obstruction-of-justice offense.”

March 25: Democrats in Congress begin demanding release of the complete Mueller report.

April 18: Barr is set to release a version of Mueller’s report with sections involving grand jury testimony, classified information, ongoing investigations and derogatory information about private individuals edited out.