Frustration grew Friday in the Dominican Republic as families of some of the 221 people killed in a nightclub roof collapse three days earlier waited for their loved ones' bodies to be identified.

Dozens of desperate relatives waited in tents at the forensic morgue in Santo Domingo, the capital city where the Jet Set club's roof caved in on hundreds of people gathered to see merengue singer Rubby Perez in the early hours of Tuesday.

Perez was on stage when disaster struck, and the 69-year-old was given a sendoff Thursday at the National Theater attended by President Luis Abinader and the singer's daughter Zulinka, who had escaped the calamity alive.

Many other families, though, still await closure before they can start the grieving process following the Caribbean nation's worst tragedy in decades.

"It is distressing, it is something you cannot imagine... the wait for the bodies is exasperating," cried Yuni Garcia, who lost her brother, a club security guard, but has yet to recover his corpse.

The office of President Abinader on Friday put the final death toll at 221, with 189 people pulled alive from the rubble of the popular nightclub now reduced to mounds of twisted steel, zinc and brick.

Aerial images of the site showed a scene resembling the aftermath of an earthquake, with a gaping hole where the club's roof had been.

A video posted on social media showed the venue, which could hold 1,700 guests, suddenly plunged into darkness while Perez was singing, followed by crashing sounds and screams.

'Days of uncertainty'

Waiting at the morgue Friday was Esperanza Dominguez, who told AFP she had yet to find her missing relative's face in photos of the dead being circulated by forensic teams working to identify the victims.

"I am worn out, I am going crazy because... of the many things I have seen," she said near a large screen displaying the names of identified victims.

Fany Martinez, 46, waited for news on her sister who lived in Spain and was in Santo Domingo on a visit.

"We have been waiting for many days, many days of uncertainty... It has been very hard, it has been very difficult for us," she said.

The extent of the tragedy has outstripped capacity.

Health Minister Victor Atallah said Thursday that "no pathology institute has the capacity to handle so many bodies so quickly."

He had vowed, however, that "no one will be left unidentified... We are going to move every last stone that needs to be moved."

Authorities said that by Friday, 191 autopsies had been done. They vowed all will be completed by Friday, and victims' remains will be returned to their families by 2:00 AM on Saturday.

Some reported errors, however.

"They gave us a body that wasn't hers," said a distraught Julio Alberto Acosta, who lost his stepdaughter in the tragedy. 

"They gave us a bag and we said we had to open it to see if it was her, but it wasn't... We want them to give us the right one so her mom can see her and go to bury her."

The preliminary victims list included a Haitian, an Italian, two French citizens and, according to the US State Department, "several" Americans.

US Secretary of State Marco Rubio spoke to Abinader Friday "to express his deepest condolences," department spokeswoman Tammy Bruce said in a statement.

The victims also included two retired Major League Baseball players and a provincial governor. 

What, why, how

Twelve extra forensic pathologists were brought on board to aid in the identification process, according to the health ministry.

The mayor's office had provided six funeral homes with 170 coffins free of charge.

The government has extended an initial three-day national mourning period for another three days to Sunday, and announced the creation of a special commission of national and foreign experts to determine the cause of the disaster.

Hundreds of rescuers, aided by sniffer dogs, have worked tirelessly since Tuesday to pull survivors from the rubble.

They called off the search for live victims late Wednesday and shifted their focus to recovering the dead.

Abinader on Friday pledged to find out "what happened, why it happened, how it happened."