SAO PAULO (REUTERS) - Part of a major expressway collapsed on Tuesday (Feb 1) above a construction site in the Brazilian city of Sao Paulo where Spain's Acciona was excavating a tunnel for a new subway line. No casualties were reported.
Television images showed a lane of the Marginal Tiete expressway caving into a widening pit alongside the construction site of the tunnel under a nearby river for the planned Line 6.
The Sao Paulo state metro operator said on its website that tunnels dug for the new subway project had been flooded.
Public safety officials said all 50 workers were able to get out of the tunnel and only two were treated for contact with dirty water that gushed through the site.
"We don't know if a water main was damaged by the excavation or if it was the bed of the Tiete River," the fire brigade's Captain Andre Elias said in a statement.
Sao Paulo Governor Joao Doria said by Twitter there had been no victims and the Spanish engineering group was asked to work with municipal authorities to reopen traffic on the expressway and resume work on the metro line as soon as possible.
Acciona is managing construction of the new metro line in a public-private partnership with Sao Paulo state and is expected to start operations by 2025.
Shares of the Spanish renewable energy and construction group erased gains and fell nearly 2 per cent after the collapse.
Representatives for the Madrid-based company did not immediately respond to questions about the incident.
Municipal traffic authority CET said on Twitter around midday that it had reopened two lanes of the Marginal Tiete running past the site, but miles of traffic remained backed up.
The planned 15km line, one of the largest infrastructure projects under way in Latin America, will join the Brasilandia district of northern Sao Paulo to the city centre.
Acciona won the contract worth €2.3 billion (S$3.5 billion) to develop and run Sao Paulo's Line 6 in October 2020.
Since setting up operations in Brazil in 1996, Acciona has worked on water treatment plants in the north-east and developed 200km of the BR-393/RJ highway.
Its other recent transportation projects in recent years include metro lines in Barcelona, Dubai and Vancouver.