The bodies of three people have been recovered from the rubble of office buildings that collapsed in the Brazilian city of Rio de Janeiro.
Three buildings - one 20 storeys high - collapsed on Wednesday night in a cloud of dust and smoke.
Rescue teams pulled six people alive from the rubble, but at least 16 people were still missing, authorities said.
The buildings were mostly used for office space during the day and were almost empty at the time of the disaster.
Rio de Janeiro Mayor Eduardo Paes discounted a gas leak as the cause of the collapse.
He said there could have been a structural failure caused by work being done on one of the buildings.
The city is struggling to address concerns over poor infrastructure as it prepares to co-host the soccer World Cup in 2014 and the Olympic Games two years later.
Last year an explosion apparently caused by a gas leak ripped through a restaurant in downtown Rio, killing three people.
