Turkey's main opposition party has claimed big election victories in the main cities of Istanbul and Ankara.
The results are a significant blow for Recep Tayyip Erdogan, who had hoped to regain control of the cities less than a year after he claimed a third term as president.
He led the campaign to win in Istanbul, where he grew up and became mayor.
But Ekrem Imamoglu, who first won the city in 2019, scored a second victory for the secular opposition CHP.
Mr Erdogan had vowed a new era in Turkey's megacity of almost 16 million people, but the incumbent mayor of Istanbul secured more than 50% of the vote, defeating the president's AK Party candidate by more than 11 points and almost one million votes.
This was also the first time since Mr Erdogan came to power 21 years ago that his party was defeated across the country at the ballot box.
In the capital Ankara, opposition mayor Mansur Yavas was so far ahead of his rival on 60% that he declared victory when less than half the votes were in. Supporters blocked all the main roads in the city, waving flags and sounding their car horns.
Significantly, the CHP - the Republican People's Party - also seized control of Turkey's fourth-biggest city Bursa and Balikesir in the north-west, and retained control of Izmir, Adana and the resort of Antalya.
