The government in Yemen says the country's main oil pipeline is still burning, after tribesmen attacked it on Saturday.

An official described the explosion, which took place near Sarwah, in Marib province, as a major setback.

A grouping of several tribes has been demanding economic compensation from the government for oil that is pumped from their territory.

The BBC correspondent in the region says that since their demands have not been met, they are trying to disrupt operations as much as possible.

The oilfield is owned by the American company, Hunt.

More than thirty people were killed in the Marib area last June, during protests at a forty-per-cent rise in oil and cooking gas, as part of IMF-imposed economic reforms.