Residents react with relief after learning that their relatives are survivors of the two collapsed buildings in the Muzema neighborhood, Rio de Janeiro, Brazil, Friday, April 12, 2019. The collapse came in a western part of the city that was particularly hard hit by heavy rains this week that caused massive flooding. (AP Photo/Leo Correa)

RIO DE JANEIRO - Brazilian authorities said Monday they knew about structural risks in the area where a pair of buildings collapsed but were unable to act due to the threat posed by organized crime.

Rio de Janeiro's mayor's office and firefighters said that 10 people, including five children, were killed when two buildings in the Itanhanga neighbourhood fell last week. The most recent casualty was an adult woman found dead early Monday morning.

"As of yet we have managed to rescue 10 people from the rubble but there is still evidence of 14 potentially missing people," Sgt. Moses Torres of the Rio fire department told The Associated Press.

"We have a lot more hope in situations like this, for example, than Brumadinho because the buildings collapsed in such a way that they can sustain life for an extended period," Torres said, referring to the January failure of a mining dam which killed 228 people.

On Monday, the state attorney general's office said that the two buildings were part of an illegal construction scheme led by militias. Such criminal organizations often take over suburban areas in Rio to build and sell unregulated housing in a process called "grilagem."

The office said that it had observed militias conducting such business in the area of the collapsed buildings as far back as 2005. But it said that courts had blocked legal actions to limit construction in the area.

In January, a specialized anti-organized crime unit conducted an operation in the area to arrest 13 individuals associated with the militias, but residents said such groups continued to tax businesses and locals.

Residents were using the condemned structures up until their collapse last Friday after days of heavy rain.

In February, Rio Mayor Marcelo Crivella said that the city had been unable to make drainage improvements in the area due to militia activity, but police had secured the neighbourhood and work was underway to resolve the issues.

"After being abandoned for so many years, I expect the area to be redeemed for Rio de Janeiro," Crivella said at the time.

He first met with community leaders in March 2017 to announce a plan to improve sanitation in the area.

A residents' association, however, said authorities had failed to make any improvements.

Rio's Secretary of Infrastructure Sebastiao Bruno said that the city will now need to demolish three buildings surrounding the collapsed structures.

Rescuers are still combing the wreckage day and night hoping to find survivors.

News from © The Associated Press, 2019