Authorities on Saturday were seeking to question the business partners of the owner of a Buenos Aires nightclub where a fire broke out during a rock concert, killing 175 people and injuring hundreds, with survivors reporting that the building's emergency exits were locked.

Club owner Omar Chaban was detained Friday and was expected to face questioning in the coming days, while police were looking for the three partners, who have not contacted investigators since the fire late Thursday.

Meanwhile, workers posted lists of the injured and dead at city hospitals, where families gathered for news of their loved ones, while tearful parents and relatives filed into the city's morgue to identify bodies.

Along with the dead, the blaze injured 714 people, at least 102 in critical condition, hospital officials said. The fire set off a stampede for the exits as the concert hall filled with thick, black smoke. Witnesses told of people struggling to force open doors, which authorities said were either tied shut or padlocked. Many of the victims died from smoke inhalation, city officials said.

Investigators said they believed one of Argentina's worst disasters began when somebody set off a flare during the concert, igniting the foam ceiling of the Cromagnon Republic club while it was crowded with about 4,000 mostly teenage fans of the Argentine rock band Los Callejeros. Argentine media reported the nightclub had a capacity of 1,500 people.

A 22-year-old survivor who gave his name only as Andres said surging crowds pushed their way toward several of the club's six doors but found some of them wouldn't open.

"Once the fire erupted, everyone ran for the doors, but there was only one very narrow one open at the exit closest to us. Another wider door next to it was locked," he said.

The Buenos Aires city government declared three days of mourning and ordered all night clubs closed during the New Year holiday weekend. Pope John Paul 11 expressed his condolences to the victims' families in a message sent to Argentine church officials.

The nightclub fire in the working-class neighborhood of Once recalled a blaze that swept a Paraguayan supermarket in August, killing 434 people in an Asuncion suburb. Authorities later said the doors were ordered shut by the store's owner to prevent looting.

In a 2003 nightclub fire in West Warwick, Rhode Island, 100 people were killed in a blaze that authorities said began when sparks from a band's pyrotechnics ignited foam used as soundproofing.