Skopje, North Macedonia. A massive fire tore through a nightclub in North Macedonia ’s eastern town of Kocani early Sunday, killing 51 people and injuring more than 100, authorities said.

The blaze broke out around 2:35 a.m. during a concert by a local pop group at the Pulse nightclub, Interior Minister Panche Toshkovski told reporters.

He said pyrotechnics caused the roof to catch fire. Videos showed chaos inside the club, with young people running through the smoke as the musicians urged people to escape as quickly as possible.

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 organizations.

Health Minister Arben Taravari said 118 people have been hospitalized, adding that he had received offers of assistance from neighboring 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.

“This is 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,” Prime Minister Hristijan Mickoski wrote on X.

“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.”

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-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 authorities would investigate the venue’s licensing and safety provisions, adding that the government had a “moral responsibility” to help prosecute anyone responsible. Police have arrested one man already, but he didn't provide details on the person's involvement.