Venezuela's President Hugo Chavez

BBC

At least seven people have been killed and dozens more injured in an explosion at Venezuela's biggest oil refinery, the local governor says.

Stella Lugo said there was no risk of further explosions at the Amuay plant in the north of the country.

Officials earlier said a gas tank had blown up during the night, damaging the plant and nearby buildings, reports the BBC.

The Amuay refinery is one of the biggest in the world, producing some 645,000 barrels a day.

Ms Lugo, governor of Falcon state, said some 48 people had been injured in the blast and were being treated in local hospitals.

She said there was still a big fire at the plant, but the situation was under control.

Earlier, Energy Minister Rafael Ramirez blamed the explosion on a gas leak.

"It was a significant explosion, there is appreciable damage to infrastructure and houses opposite the refinery," he said.

Analysts say refineries in Venezuela, South America's biggest oil producer, have suffered from a long list of problems including power failures and accidents.