SKOPJE: A fire tore through a nightclub in North Macedonia early Sunday, killing 59 people, apparently after on-stage fireworks set the place ablaze, authorities said, announcing arrest warrants for four people.

They said 155 injured people had been taken to hospitals across the country, 18 of them in critical condition. Some of the serious cases were to be taken to other European countries for treatment.

The blaze started in the Club Pulse in the eastern town of Kocani, as the place was packed with more than 1,000 mostly young fans attending a concert by a popular hip-hop duo called DNK.

“Initially we didn’t believe there was a fire. Then there was huge panic in the crowd and a stampede to get out,” one young woman told local media outside a hospital in the capital Skopje.

Fire crews and paramedics responded quickly and “tried to resuscitate people ... but it wasn’t enough,” said the woman, who was waiting outside for one of her friends, who was being treated for burns to his hand.

The fire was probably caused by the use of pyrotechnic devices “used for light effects at the concert,” said Interior Minister Pance Toskovski, who visited the scene with Prime Minister Hristijan Mickoski.

“Sparks caught the ceiling, which was made of easily flammable material, after which the fire rapidly spread across the whole discotheque, creating thick smoke,” Toskovski said.

The Interior Ministry announced that arrest warrants had been issued for four people in relation to the tragedy, and a criminal investigation opened.

“There are 59 persons deceased of which 35 are identified. Of the identified, 31 persons are from Kocani and four from Stip,” Toskovski said.

“The number of wounded, according to latest information up to noon, is 155 persons who are in hospitals across the country,” Toskovski said.

“Preparations are being made to transport people seriously injured in the fire in Kocani to top hospitals in several European countries,” the head of North Macedonia’s Crisis Center, Stojanche Angelov, said.

The head of the Kocani hospital, Kristina Serafimovska, told media that the patients being treated there were aged between 14 and 25.

“Seventy of the patients have burns and carbon monoxide poisoning,” she said.

One of the members of the DNK duo that had performed, Vladimir Blazev, had burns to his face and needed assistance breathing, his sister told local media outlets.

“This is a difficult and very sad day” for the country, Mickoski wrote on his Facebook account.

“The loss of so many young lives is irreparable, and the grief of their families, their loved ones and their friends is immeasurable,” he said.