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Fires continue to burn at the site of a massive explosion at Venezuela's biggest oil refinery.

In one of the industry's deadliest accidents, the blast left 41 people dead, including civilians and National Guard troops.

Caused by a gas leak, the explosion also damaged more than 200 homes in the nearby area.

President Hugo Chavez visited the refinery on Sunday (August 26), insisting officials would get to the bottom of what happened.

The explosion comes after years of accidents and outages at plants run by the state oil producer.

Chavez was quick to respond to accusations of mismanagement.

SOUNDBITE: PRESIDENT OF VENEZUELA HUGO CHAVEZ SAYING (Spanish):

"It would be very sad, very sad, if some Venezuelans were to try to use the pain, the pain that envelops us, the pain of the families, the sacrifice of the victims. For what? Well, to profit from it. That would be very sad. However, the reason for the problem is what most interests me at this moment. From the very first moment."

The president later attended mass in honour of those who lost their lives.

With several people still unaccounted for and at least 35 in hospital, officials said the death toll could rise.