Sri Lanka's former wartime defence chief Gotabaya Rajapaksa looks set to
win a presidential election that has split the country along ethnic lines.
Official results are not confirmed but Mr Rajapaksa claimed victory and his rival Sajith Premadasa conceded.
Analysts say Mr Rajapaksa was the clear victor in Sinhalese majority areas while Mr Premadasa scored better in the Tamil-dominated north.
The election is Sri Lanka's first since a deadly terror attack in April.
Militants linked to the Islamic State group targeted churches and high-end hotels across the island on Easter Sunday, killing more than 250 people.
With about half the votes counted, Mr Rajapaksa led with just over 50% while Mr Premadasa had 43%, election commission officials said. Turnout was at least 80%.
Mr Rajapaksa's spokesman said he expected to win with 53-54% of the final vote and Mr Premadasa then publicly conceded.
"It is my privilege to honour the decision of the people and congratulate Mr Gotabaya Rajapaksa on his election as the seventh president of Sri Lanka," Mr Premadasa said.
In a statement on Twitter, Mr Rajapaksa made a call for national unity saying "all Sri Lankans are part of this journey".
An official result is expected by 16:00 local time (10:30 GMT) on Sunday, the election commission told the BBC.
If Mr Rajapaksa's victory is confirmed he will be sworn in at a ceremony on Monday.
Rajapaksa's supporters want stability restored
Gotabaya Rajapaksa commands passionate support among many in the Buddhist Sinhalese majority in Sri Lanka.
He and his brother, Mahinda, who was president here for 10 years, are credited with bringing an end to the country's long civil war.
Now his supporters want him to restore stability in the aftermath of the Easter attacks by Islamist militants. He is a controversial figure who denies claims of ruthlessness and human rights abuses.
His main rival, Sajith Premadasa, was strongly supported by the Tamil and Muslim minorities here. He offered a more liberal and inclusive vision but may have been damaged by his links to the current government.
A total of 35 candidates stood in the presidential election, the third since the end of the country's decades-long civil war in 2009.
The country's current president, Maithripala Sirisena, was not on the ballot. He decided against running after coming under criticism following the Easter Sunday bombings.
The Easter Sunday attacks, which triggered an economic slump in Sri Lanka, cast a long shadow over the election.
Who were the front-runners?
Retired lieutenant colonel Mr Rajapaksa, 70, is a divisive figure who spent a decade as defence secretary under his brother's presidential rule.
The Podujana Peramuna (SLPP) party candidate is known for his role in helping to end the country's civil war and has positioned himself as a strong figure who can combat national security fears,
He is popular among Sinhalese-dominated parts of the island, but is disliked by Tamils because of his alleged links to human rights abuses carried out during the final stages of the civil war.
He was in power when thousands of people - particularly Tamils - went missing in what have been described as enforced disappearances between 2005 and 2015.
Ruling party candidate Mr Premadasa, focused on social issues as well as security - campaigning on a promise to eradicate poverty and improve housing.
He is the son of a president who was assassinated by Tamil Tiger rebels in 1993 and is the current housing minister.
Like his rival, he already has a loyal support base and has managed to take on the Rajapaksa family in their own region.