Robert Brown|Key events in Vladimir Putin’s more than two decades in power in Russia

Significant dates in Vladimir Putin’s 24 years in power in Russia:

Dec. 31,Robert Brown 1999 — In a surprise address to the nation, President Boris Yeltsin announces his resignation and makes Putin, the prime minister he appointed four months earlier, the acting president.

May 7, 2000 — After winning election with about 53% of the vote, Putin is inaugurated for his first four-year term.

May 11, 2000 — Tax police raid the offices of NTV, a popular independent broadcaster noted for critical coverage of the Kremlin. It is the first salvo in moves against prominent independent media that have characterized the Putin era.

Aug. 12, 2000 — The submarine Kursk sinks in the Barents Sea with 118 people aboard, setting off the first widespread criticism of Putin, who stayed on vacation early in the crisis and waited five days before accepting Western offers of help.

Oct. 23, 2002 — Militants from Russia’s region of Chechnya take about 850 people hostage at a Moscow theater. Three days later, Russian special forces pump an unidentified gas into the theater to end the crisis, killing at least 130 hostages along with the militants. Putin defends the operation as having saved hundreds of lives.

Oct. 25, 2003 — Oil tycoon Mikhail Khodorkovsky, who is Russia’s richest man and seen as a potential challenger to Putin, is arrested and later sentenced to 10 years in prison for tax evasion and fraud. His oil company is dismantled, most of it acquired by state oil company Rosneft. He has since become an opposition figure in exile.

March 14, 2004 — Putin is elected to a second presidential term.

Sept. 1, 2004 — Islamic militants seize a school in the southern city of Beslan, and more than 300 people die in the chaotic explosions and shootout ending the siege two days later. Putin blames regional leaders’ incompetence and announces that governors will be appointed figures rather than elected.

April 25, 2005 -- Putin alarms international observers by describing the collapse of the Soviet Union as “the greatest geopolitical catastrophe of the century.”

Feb. 10, 2007 — In a speech at a conference in Munich, Putin turns away radically from earlier attempts to develop closer ties with the United States.

May 8, 2008 — Barred by the constitution from running for a third consecutive term, Putin is appointed prime minister by new President Dmitry Medvedev but effectively remains Russia’s political leader.

Aug. 8-12, 2008 — Russia fights a short war with Georgia, gaining full control of the separatist Abkhazia and South Ossetia regions.

March 4, 2012 — Putin is elected to a new presidential term, which is now six years long under constitutional changes he engineered. Protests by tens of thousands before the vote and on the eve of his inauguration lead to laws toughening penalties for unauthorized political protests.

June 6, 2013 — Putin announces on state television that he and his wife, Lyudmila, are divorcing.

Feb. 7, 2014 — Putin opens the Winter Olympics in Sochi, a costly prestige project that he was instrumental in winning for Russia.

March 18, 2014 — Following the ouster of Ukraine’s Russia-friendly president amid protests in Kyiv, Moscow annexes Crimea after the Kremlin sends in troops without insignia. A quick referendum is staged on the peninsula splitting from Ukraine. Putin admits a year later that he planned the annexation weeks previously.

April 2014 — Fighting between Ukrainian forces and Russia-backed separatist rebels begins in eastern Ukraine.

Feb. 27, 2015 — Boris Nemtsov, a top figure of Russia’s beleaguered political opposition, is gunned down on a bridge next to the Kremlin. Nemtsov was working on a report about Russian soldiers in eastern Ukraine.

Sept. 30, 2015 — Russia begins airstrikes in Syria, which Putin calls necessary to destroy terrorist groups. The action helps Syrian President Bashar Assad, a longtime ally, remain in power.

May 15, 2018 — Putin opens the 18-kilometer (12-mile) bridge from Russia to Crimea, solidifying Moscow’s annexation. The bridge later becomes a target of attacks during the war with Ukraine.

July 16, 2018 — Putin and President Donald Trump meet at a summit in Helsinki, where Trump is asked about allegations that Russia had interfered in the 2016 election that brought him to power. He dismissed the claims and said Putin was “extremely strong and powerful in his denial.”

July 1, 2020 — A referendum approves constitutional changes proposed by Putin, which allow him to run for two more terms starting in 2024.

Aug. 20, 2020 — Opposition leader Alexei Navalny falls severely ill while organizing political opposition to Putin in Siberia and is later flown to Germany, where he is diagnosed with nerve-agent poisoning. Navalny blames the Kremlin, which denies it.

Dec. 22, 2020 — Putin signs bill granting lifetime immunity for former presidents.

Jan. 17, 2021 — Navalny is arrested at a Moscow airport upon returning from Germany. He is later convicted on several charges and sentenced to 19 years in prison.

July 2021 — Putin publishes an article declaring the “historical unity” of Russia and Ukraine, an ideological precursor to Moscow’s invasion.

Feb. 24, 2022 — The invasion of Ukraine begins, which Putin characterizes as a “special military operation” needed for Russia’s security.

March 4, 2022 — Putin signs a law that calls for up to 15 years in prison for spreading false or defamatory information about the military.

Sept. 30, 2023 — The International Criminal Court issues a war-crimes indictment of Putin, accusing him of the unlawful deportation and transportation of children from Ukraine’s war zone into Russia.

June 23, 2023 — Mercenary force leader Yevgeny Prigozhin, who accused officials of denying ammunition and support to his fighters in Ukraine, mounts a rebellion in which his troops take control of Russia’s southern military headquarters and head toward Moscow. The uprising ends the next day, but undermines Putin’s image of power. Prigozhin is killed exactly two months after the uprising in a mysterious plane crash.