Brazilian police officials said Monday they've made three detentions and are seeking a fourth person in connection with a blaze that ripped through a nightclub in southern Brazil over the weekend, killing 231 people.

Insp. Ranolfo Vieira Junior said at a news conference that the detentions are for investigative purposes and those detained can be held up to five days. He declined to identify those detained or the fourth person sought, but the Brazilian newspaper Zero Hora quotes lawyer Jader Marques saying his client Elissandro Spohr, a co-owner of the club, had been held.

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The paper also says police detained two band members who were on stage when the blaze broke out and were thought to have used pyrotechnics in their act.

A military brigade official said Monday the death toll now stands at 231 people in the early Sunday blaze in the Kiss nightclub in Santa Maria, a university town of about 260,000 people in southern Brazil. Many of the victims were under 20 years old, including some minors. Most victims died from smoke inhalation rather than burns.

Family members and friends stand around coffins containing the remains of victims after the bodies were identified at a gymnasium in Santa Maria city. (Nabor Goulart/Associated Press)

Police have said they think the pyrotechnics ignited sound insulation on the ceiling. There was no fire alarm, no sprinklers, no fire escape. In violation of state safety codes, fire extinguishers were not spaced every 1,500 square feet, and there was only one exit.

Many of the dead were found in the club's two bathrooms, where people had fled apparently because the blinding smoke caused them to believe the doors were exits.

"It was terrible inside — it was like one of those films of the Holocaust, bodies piled atop one another," said police Insp. Sandro Meinerz. "We had to use trucks to remove them. It took about six hours to take the bodies away."

Survivors and another police inspector, Marcelo Arigony, said security guards briefly tried to block people from exiting the club. Brazilian bars routinely make patrons pay their entire tab at the end of the night before they are allowed to leave.

'The roof was burning'

"It was chaotic and it doesn't seem to have been done in bad faith because several security guards also died," Arigony told The Associated Press.

Firefighters responding to the blaze initially had trouble getting inside the Kiss nightclub because "there was a barrier of bodies blocking the entrance," Guido Pedroso Melo, commander of the city's fire department, told the O Globo newspaper.

Authorities said band members who were on the stage when the fire broke out later talked with police and confirmed they used pyrotechnics during their show.

Guitarist Rodrigo Martins told Radio Gaucha that the band, Gurizada Fandangueira, started playing at 2:15 a.m. "and we had played around five songs when I looked up and noticed the roof was burning."

"It might have happened because of the Sputnik, the machine we use to create a luminous effect with sparks. It's harmless, we never had any trouble with it," he said. "When the fire started, a guard passed us a fire extinguisher, the singer tried to use it but it wasn't working."

Accordion player among victims

He confirmed that accordion player Danilo Jacques, 28, died, while the five other members made it out safely.

'It was complete panic, and it took a long time for people to get out, there were so many dead.'—Survivor Luana Santos Silva

Survivor Michele Pereira told the Folha de S. Paulo newspaper that she was near the stage when members of the band lit some sort of flare 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."

Police Insp. Meinerz, who co-ordinated the investigation at the nightclub, said one band member died after escaping because he returned inside the burning building to save his accordion. The other band members escaped alive because they were the first to notice the fire.

Television images from Santa Maria showed black smoke billowing out of the Kiss nightclub as shirtless young men who attended the university party joined firefighters using axes and sledgehammers to pound at the hot-pink exterior walls, trying to reach those trapped inside.

Bodies strewn in the street

Teenagers sprinted from the scene after the fire began, desperately seeking help. Others carried injured and burned friends away in their arms. About half of those killed were men.

An estimated 500 people were in the Boate Kiss nightclub when the fire broke out early Sunday. (Edison Vara/Reuters)

Bodies of the dead and injured were strewn in the street and panicked screams filled the air as medics tried to help. There was little to be done; officials said most of those who died suffocated within minutes.

"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," survivor Luana Santos Silva told the Globo TV network.

The fire spread so fast inside the packed club that firefighters and ambulances could do little to stop it, Silva said.

A community gym soon became a horror scene, with body after body lined up on the floor, partially covered with black plastic as family members identified kin.

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Outside the gym, police held up personal objects — a black purse, a blue high-heeled shoe — as people seeking information on loved ones crowded around hoping not to recognize anything being shown them.

The party was organized by students from several academic departments at the Federal University of Santa Maria. Such organized university parties are common throughout Brazil.

Brazil President Dilma Rousseff arrived Sunday to visit the injured after cutting short her trip to a Latin American-European summit in Chile.

"It is a tragedy for all of us," said Rousseff, who began her political career in the state where the tragedy took place.