Blasts rock world's biggest oil rig

At least one person has died and nine are missing after three powerful blasts rocked the world's biggest oil rig.

At least one person has died and nine are missing after three powerful blasts rocked the world's biggest offshore oil platform

The 40-story rig owned by Brazil's state oil giant Petrobras is anchored off the coast of Rio De Janeiro in Brazil.

"As for the nine people missing, there is a very small chance that they will survive," Petrobras President Henri Philippe Reichstul said at a news conference in Macae, its headquarters for offshore operations in Rio.

Some 175 people were on the rig at the time of the first explosion, but survivors were transferred to a neighboring platform. A firefighting team of 25 people was left aboard.

It is not clear what caused the explosion but Reichstul said the $350m platform, the world's largest in terms of capacity, could yet sink.