Macedonia's worst tragedy in recent memory left an emotional president struggling to "believe how this happened".
A massive fire in a nightclub in North Macedonia's southern town of Kocani has killed 59 people and injured 155, authorities say.
The blaze began about 2.35am (6.35pm AEDT) on Sunday during a concert by a local pop group, Interior Minister Panche Toshkovski told reporters.
Officials said 39 of the dead had so far been identified, adding that 18 of those injured were in critical condition.
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The pre-dawn blaze in the eastern town of Kocani left mostly young people dead and injured due to burns, smoke inhalation and a stampede in the desperate effort to reach the building's single exit. People as young as 16 were among the casualties, officials said.
Videos showed sparkling pyrotechnics on the stage hitting the ceiling followed by scenes of chaos inside the club, with young people running through the smoke as the musicians urged them to escape as quickly as possible.
Throughout Sunday, relatives gathered in front of hospitals and city offices in Kocani, some 115 kilometres east of the capital, Skopje, begging authorities for more information.
Local resident Dragi Stojanov was informed that his 21-year-old son Tomce had died in the fire.
"He was my only child. I don't need my life anymore... 150 families have been devastated," he said.
"Children burnt beyond recognition. There are corpses, just corpses inside (the club)."
Officials said the injured have been taken to hospitals around the country, including the capital, Skopje, many with severe burns. The effort was being assisted by multiple volunteer organisations.
The fire caused the roof of the single-story building to partially collapse, revealing the charred remains of wooden beams and debris. Police cordoned off the site and sent in evidence gathering teams in an operation also involving state prosecutors.
Toshkovski said 15 people were detained for questioning after a preliminary inspection revealed the club was operating without a proper license. He said the number of people inside the club was at least double its official capacity of 250.
Health Minister Arben Taravari said 118 people have been hospitalised, adding that he had received offers of assistance from neighbouring countries, including Albania, Bulgaria and Greece.
"All our capabilities have been put to use, in a maximum effort to save as many lives as possible of the young people involved in this tragedy," Taravari told reporters, at times looking visibly shaken.
This is the worst tragedy in recent memory to befall the landlocked nation, whose population is less than 2 million.
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President Gordana Siljanovska-Davkova visited burn victims at a hospital in Skopje and spoke to parents waiting outside the building.
"It's terrible ... hard to believe how this happened," she said, her voice halting with emotion.
"We must give these young people courage to continue."
Prime Minister Hristijan Mickoski said it was "a difficult and very sad day for Macedonia".
"The loss of so many young lives is irreparable, and the pain of the families, loved ones and friends is immeasurable," he wrote on X, formerly Twitter.
"The people and the government will do everything in their power to at least slightly alleviate their pain and help them in these most difficult moments."
The prime minister also said it had been "the most difficult day of my life," and that the country must defeat corruption.
"I entered politics to change something. I encountered a deeply corrupt system that has been created and nurtured for decades, which includes people from all parties, from all profiles. If that system does not collapse, this country will never exist," he said in a statement.
North Macedonia's government ordered a sweeping inspection to be carried out at all nightclubs and cabarets across the country over the next three days.
Pyrotechnics have often been the cause of deadly fires in nightclubs, including the one at the Colectiv club in Bucharest, Romania, in 2015 in which 64 people died.
Family members gathered in front of hospitals and Kocani's city offices begging authorities for more information.
The club was in an old building that was previously a carpet warehouse and has been running for several years, according to local media MKD.
The fire caused the roof of the single-storey building to partially collapse, revealing the charred remains of wooden beams and debris.
Condolences poured in from leaders around Europe as well as from the office of Pope Francis who has been in hospital for the last month, where he is fighting double pneumonia.
The European Union's foreign policy chief, Kaja Kallas, posted on X that she was "deeply saddened" and said the 27-nation bloc "shares the grief and pain of the people of North Macedonia." North Macedonia is a candidate for EU membership.
Condolences also poured in from politicians across the region, including Albania's Prime Minister Edi Rama, the European Commissioner for Enlargement, Marta Kos, and Ukrainian President Volodymyr Zelenskyy.
"I wish those who were injured a speedy recovery. Ukraine mourns alongside our (North) Macedonian friends on this sad day," Zelenskyy wrote on X.
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