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20-story buildings collapse in Rio, cause deaths

Ari Versiani / AFP - Getty Images

Firefighters look for victims amid the rubble of a building that collapsed in downtown Rio de Janeiro, Brazil, on Wednesday, Jan. 25, 2012.

Felipe Dana / AP

Rescue workers carry an injured victim on Wednesday night.

RIO DE JANEIRO -- Two downtown buildings collapsed Wednesday, leaving at least two dead inside the wreckage. Rescue crews pulled four people alive from the debris, officials said. One building was 20 stories tall; the other, 10, Reuters reported. A loud explosion preceded the collapse, witnesses said.

There was a strong smell of gas in the area, officials said. However, a gas leak likely didn't cause the blast, Rio's mayor said.

Vanderlei Almeida / AFP - Getty Images

Firefighters with searchlights look for victims amid the rubble of a building on Wednesday night.

Vanderlei Almeida / AFP - Getty Images

Top view of firefighters looking for victims amid the rubble of a building that collapsed in downtown Rio de Janeiro on Wednesday night.