SANTO DOMINGO — Rescuers raced to find survivors early on Wednesday after the roof of a Dominican Republic nightclub collapsed during a concert by popular singer Rubby Perez, one of the at least 120 people killed in the disaster.

Rescue workers were pressing on with the search effort, which more than 24 hours after the roof caved in, began to be limited more to recovering bodies.

Renowned singer Perez, who was on stage at the popular Jet Set nightclub when the roof collapsed shortly after midnight on Tuesday, was one of those killed, according to his manager.

"We are waiting for the children to reach an agreement for the funeral," Perez's manager Enrique Paulino told AFP.

About 370 rescue personnel combed mounds of fallen bricks, steel bars and tin sheets for survivors. Also among the dead was 51-year-old retired Major League Baseball pitcher Octavio Dotel, who won a World Series in 2011 with the St Louis Cardinals.

He was rescued alive but died of his injuries while being taken to hospital, local media reported.

Huge crowd

Local media said there were between 500 and 1,000 people in the club when the disaster struck at around 12:44 am on Tuesday.

The club has the capacity for 700 people seated and about 1,000 people standing. Dozens of ambulances ferried the injured to hospital, as scores of people gathered outside the venue desperately seeking news of their loved ones.

Perez was on stage when there was a blackout and the roof came crashing down, according to eyewitness reports. Perez's daughter Zulinka told reporters she had managed to escape after the roof collapsed, but he did not.

Also among the dead was the governor of the Monte Cristi municipality, Nelsy Cruz, according to Dominican Republic President Luis Abinader.

The president visited the scene and declared three days of national mourning.

"As long as there is hope for life, all authorities will be working to recover or rescue these people," he said earlier.

Dozens of family members flocked to hospitals for news.

"We are desperate," Regina del Rosa, whose sister was at the concert, told SIN. "They are not giving us news, they are not telling us anything."

Authorities have issued a call for Dominicans to donate blood.