Fire ripped through a packed nightclub early on Sunday in the North Macedonian town of Kocani, killing 59 people and injuring more than 100, after sparks ignited the roof over a live band.
Arrest warrants have been issued for four people in connection with the fire, said interior minister Pance Toskovski. State news agency Mia said that police have detained the owner of the club over the incident.
One video from the event, verified by Reuters, showed a band playing on stage flanked by two flares, the white sparks of which set the ceiling alight.
Friends and family were separated in a panicked rush to the exits.
"Everyone was trying to save themselves," survivor Marija Taseva, 22, told local TV 5.
As she tried to escape, Taseva fell to the ground and people trod over her, leaving her with an injury on her cheek. In the rush, she lost contact with her sister, who is still missing.
"We can't find her in any hospital," she said.