BUCHAREST, Romania (AP) — An explosion and ensuing flames on a stage at a Bucharest nightclub on Friday left 27 people dead and 180 hospitalized with injuries, Romania's interior minister said.

Interior Minister Gabriel Oprea said the explosion occurred at Colectiv club, located in a basement in downtown Bucharest, a city of 3 million people.

Witnesses told Antena 3 TV that there were between 300 to 400 mostly young people at the club and only one exit door when the metal band Goodbye to Gravity was performing and a "pyrotechnical show" went awry. The station reported that people panicked and rushed for the exit.

Media reported that emergency services arrived 11 minutes after the first call at 10:32 p.m. (2032 GMT) .

Digi 24 television station cited witnesses who said the explosion came after a spark on stage ignited some polystyrene decor. Victor Ionescu, who was at the club with his girlfriend, told Antena 3 TV by telephone that there were huge flames after the explosion.

"People were fainting, they were fainting from the smoke. It was total chaos, people were trampling on each other," he said.

A young man filmed by Antena 3 said that flames engulfed clubgoers, burning their skin and hair.

Raed Arafat, a government health ministry official, said that people were treated for burns, smoke inhalation and lesions at hospitals around the capital.

"It is a tragedy without precedent and it is an intervention without precedent," he said.

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.

President Klaus Iohannis sent his condolences and said he was considering declaring a day of national mourning.

The ministry said there were 60 ambulances and fire engines were sent to the scene and a mobile hospital had been set up outside. Some 50 people were taken to the Floreasca emergency hospital, the ministry said.

Health Minister Nicolae Banicoiu called for people to donate blood to help the injured.