RIO DE JANEIRO — A fire ignited by a flare from a rock band’s pyrotechnic spectacle swept through a nightclub filled with more than 1,000 university students early Sunday morning in Santa Maria, Brazil, leaving at least 233 people dead, police said.
Colonel Guido Pedroso de Melo, Fire Department commander in Santa Maria, said security guards had locked secondary exits, which intensified the panic as people in the club stampeded for the doors. Most of the victims died of smoke inhalation, investigators said.
Survivors described a scene of horror as patrons rushed for the main exit, which was partly blocked by bodies. ‘‘I only got out because I am strong,’’ said Ezequiel Corte Real, 23, who helped others escape the blaze.
The disaster ranks among the deadliest nightclub fires in history, comparable to the 2003 blaze at The Station nightclub in Rhode Island that killed 100 people, one in 2004 in Buenos Aires in which 194 were killed, and a fire at a club in China in 2000 in which 309 people died. In 1942, a fire at the Cocoanut Grove nightclub in Boston killed 492 people.
The loss of life in Santa Maria, which is in the relatively prosperous southern state of Rio Grande do Sul, shocked the country. President Dilma Rousseff canceled appointments at a summit in Chile to travel to Santa Maria, a city of about 260,000 residents that is known for its cluster of universities.
Health workers hauled bodies from the club, called Kiss, to hospitals in Santa Maria throughout Sunday morning. Some of the survivors were taken to the nearby city of Porto Alegre to be treated for burns. Valdeci Oliveira, a local legislator, said he saw piles of bodies in the nightclub’s bathrooms, which were apparently mistaken for exits.
The circumstances surrounding the blaze, including the use of pyrotechnics and the reports of locked exits, are expected to raise questions about whether the club’s owners had been negligent.
While it is not clear why exits were locked, it is common across Brazil for nightclubs and bars to have customers to pay their entire tab upon leaving, rather than on a per-drink basis.
Mayor Cezar Schirmer declared a 30-day period of mourning, and Tarso Genro, the state governor, said officials were investigating the cause of the disaster.
More broadly, the blaze may focus attention on issues of accountability in Brazil and point to relaxed enforcement of safety measures in an economy that is on solid footing.
Witnesses said the fire started about 2 a.m. after a rock band, Gurizada Fangangueira, began performing. Most of the patrons were students in the agronomy and veterinary medicine programs in a local university who were attending a party.
The band, based in Santa Maria, advertises the use of pyrotechnics in its publicity materials. At least one member of the five-person band was said to have been killed.
‘‘The smoke spread very quickly,’’ said Aline Santos Silva, 29, a survivor, in comments to the GloboNews television network. ‘‘Those who were closest to the stage, where the band was playing, had the most difficulty getting out.’’
‘‘There was so much smoke and fire, it was complete panic, and it took a long time for people to get out, there were so many dead,’’ Silva said. She said the fire spread so fast that firefighters could do little to stop it.
Another survivor, Michele Pereira, told the Folha de S. Paulo newspaper that she was near the stage when members of the band lit flares that started the conflagration.
‘‘The band that was onstage began to use flares and, suddenly, they stopped the show and pointed them upward,’’ she said. ‘‘At that point, the ceiling caught fire. It was really weak, but in a matter of seconds it spread.’’
Guitarist Rodrigo Martins told Radio Gaucha that the band “had played around five songs when I looked up and noticed the roof was burning.’’
The scene recalled the 2003 fire at The Station nightclub in West Warwick, R.I., at which the rock band Great White was performing. During the show, pyrotechnics set fire to flammable soundproofing foam that lined the walls and ceiling, killing 100 and injuring 200.
In the Santa Maria fire, photographs taken shortly after the blaze and posted on the websites of local news organizations showed frantic scenes in which people on the street outside the nightclub pulled bodies from the charred building.
With smoke pouring from the club, young men joined firefighters using axes and sledgehammers in pounding at windows and walls to free those trapped inside. Some of those who escaped carried injured and burned friends in their arms.
Most of the dead were asphyxiated, said Dr. Paulo Afonso Beltrame, a professor at the medical school of the Federal University of Santa Maria who went to the city’s Caridade Hospital to help victims.
Beltrame said he was told the club had been filled far beyond its capacity because of the party. Rodrigo Moura, identified by the newspaper Diario de Santa Maria as a security guard at the club, said it was at its maximum capacity of between 1,000 and 2,000, and partygoers were pushing and shoving to flee, Associated Press said.
‘‘The toxic smoke made people lose their sense of direction so they were unable to find their way to the exit,’’ Beltrame said.
In the hospital, the doctor ‘‘saw desperate friends and relatives walking and running down the corridors looking for information,’’ he said, calling it ‘‘one of the saddest scenes I have ever witnessed.’’
Government officials focused Sunday on the grief in Santa Maria. ‘‘How many families are now searching for their young one?’’ asked Maria do Rosario Nunes, a Cabinet minister who is Rousseff’s top human rights official.
The tragedy occurred in part of Brazil where Rousseff made her political career before rising to national prominence .
Before departing from the summit in Chile on Sunday, she appeared distraught, crying as she absorbed details of the blaze. ‘‘This is a tragedy,’’ she said, ‘‘for all of us.’’