Interior Minister Gabriel Oprea initially said an explosion occurred at a club located in a basement in downtown Bucharest, but authorities at the scene later said there had only been a fire.
The incident occured during a Halloween party at the Colectiv nightclub, which had over 400 people inside at the time, Sky News reported.
Witnesses at the scene told Digi 24 television station the fire began after a spark on a stage where the metal band Goodbye to Gravity was performing ignited some of the polystyrene decor.
Some victims left the scene with severe burns, while others were being resuscitated on the street outside the venue, according to Romanian media reports.
Victor Ionescu, who was at the club with his girlfriend, told Romania’s Antena 3 TV by telephone that there were huge flames inside the packed club.
“People were fainting, they were fainting from the smoke. It was total chaos, people were trampling on each other,” he said. “It was a tragedy that could have been avoided if there had been more organization from the emergency services.”
A government health ministry official, said that people were treated for burns, smoke Breathing and lesions at hospitals around the capital. “It is a tragedy without precedent and it is an intervention without precedent,” he said.
Romanian President Klaus Iohannis wrote on his Facebook page that he was “shaken and deeply hurt by the tragic event. It is a very sad moment for us all, for our nation and for me personally.” He said he was considering declaring a day of national mourning.
According to the Bucharest-based metal band’s Facebook page, lead singer Andrei Gault was the 2008 winner of “Megastar,” a Romanian show similar to “American Idol.” The band has five members and has released two albums since it formed in 2011.
The government is meeting later Saturday and is expected to announce three days of mourning.