Greece's opposition party New Democracy look set to win the country's snap general election.
Prime Minister Alexis Tsipras, who leads the leftist Syriza party, has called leader Kyriakos Mitsotakis to concede victory, reports say.
Greece's interior ministry forecasts 39.7% of the vote for New Democracy, and 31.5% for Syriza.
That would give New Democracy an outright majority, as the winner receives 50 extra seats in parliament.
So far about 45% districts have returned their results, so the numbers may still change.
Polls closed at 19:00 local time (16:00 GMT), after a day of soaring temperatures which raised concerns about turnout - which is currently predicted to be about 56%.
Voting is technically compulsory in Greece, but is not enforced. Many residents flocked to the beaches or sheltered at home as temperatures exceeded 35C in places.
Greeks are going to the polls to elect a new parliament, with the centre-right opposition mounting a strong challenge to the leftist government, BBC reported.
The New Democracy party of Kyriakos Mitsotakis is hoping to end more than four years of rule by Prime Minister Alexis Tsipras's Syriza party.
Mr Tsipras called snap elections soon after suffering an electoral defeat in May's European elections.
Polling stations opened at 07:00 local time (04:00 GMT).
It is Greece's sixth election since the global financial crisis in 2008.
The crisis triggered a succession of financial bailouts, with the Greek economy shrinking by 28% between 2008 and 2016, and increasing unemployment has thrown many Greeks into poverty.
Greece exited the bailout programme in August of last year and growth has returned.
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