Ankara. Turkish President Recep Tayyip Erdogan won reelection Sunday, extending his increasingly authoritarian rule into a third decade as the country reels from high inflation and the aftermath of an earthquake that leveled entire cities.

A third term gives Erdogan, a polarizing populist, an even stronger hand domestically and internationally, and the election results will have implications far beyond the capital of Ankara. Turkey stands at the crossroads of Europe and Asia, and it plays a key role in NATO.

With more than 99 percent of ballot boxes opened, unofficial results from competing news agencies showed Erdogan with 52 percent of the vote, compared with 48 percent for his challenger, Kemal Kilicdaroglu. The head of Turkey’s electoral board confirmed the victory, saying that even after accounting for outstanding votes, the result was another term for Erdogan.

In two speeches — one in Istanbul and one in Ankara — Erdogan thanked the nation for entrusting him with the presidency for five more years.

“We hope to be worthy of your trust, as we have been for 21 years,” he told supporters on a campaign bus outside his home in Istanbul in his first comments after the results emerged.

He ridiculed his challenger for his loss, saying “bye bye bye, Kemal,” as supporters booed. He said the divisions of the election are now over, but he continued to rail against his opponent as well as the former co-leader of the pro-Kurdish party who has been imprisoned for years over alleged links to terrorism.

“The only winner today is Turkey,” Erdogan said to hundreds of thousands gathered outside the presidential palace in Ankara, promising to work hard for Turkey's second century, which he calls the “Turkish century.” The country marks its centennial this year.

Kilicdaroglu campaigned on promises to reverse Erdogan’s democratic backsliding, to restore the economy by reverting to more conventional policies and to improve ties with the West. He said the election was “the most unjust ever,” with all state resources mobilized for Erdogan.

“We will continue to be at the forefront of this struggle until real democracy comes to our country,” he said in Ankara. He thanked the more than 25 million people who voted for him and asked them to “remain upright.”

The people have shown their will "to change an authoritarian government despite all the pressures,” he said.

Supporters of Erdogan took to the streets to celebrate, waving Turkish or ruling party flags, honking car horns and chanting his name. Celebratory gunfire was heard in several Istanbul neighborhoods.

Erdogan, who has been at Turkey’s helm for 20 years, came just short of victory in the first round of elections on May 14. It was the first time he failed to win an election outright, but he made up for it Sunday.

Congratulations poured in from world leaders, including Russian President Vladimir Putin and Ukrainian President Volodymyr Zelenskyy, whose countries are at war in Ukraine.

Putin said Erdogan's victory was “clear evidence” that the Turkish people support his efforts to “strengthen state sovereignty and pursue an independent foreign policy.”

Zelenskyy said he was counting on building the partnership between the two countries and strengthening cooperation "for the security and stability of Europe.”

U.S. President Joe Biden said he looked forward "to continuing to work together as NATO allies on bilateral issues and shared global challenges.”

Erdogan, a 69-year-old Muslim, is set to remain in power until 2028.

He transformed the presidency from a largely ceremonial role to a powerful office through a narrowly won 2017 referendum that scrapped Turkey’s parliamentary system of governance. He was the first directly elected president in 2014, and won the 2018 election that ushered in the executive presidency.

The first half of Erdogan’s tenure included reforms that allowed the country to begin talks to join the European Union, and economic growth that lifted many out of poverty. But he later moved to suppress freedoms and the media and concentrated more power in his own hands, especially after a failed coup attempt that Turkey says was orchestrated by the U.S.-based Islamic cleric Fethullah Gulen. The cleric denies involvement.

Erdogan's rival was a soft-mannered former civil servant who has led the pro-secular Republican People’s Party, or CHP, since 2010.

In a frantic effort to reach out to nationalist voters in the runoff, Kilicdaroglu vowed to send back refugees and ruled out peace negotiations with Kurdish militants if he is elected.