BAGHDAD (Reuters) - Saboteurs blew up a major oil pipeline in Iraq on Thursday, cutting exports from the south of the country for the first time in years, a South Oil Company (SOC) official told Reuters.

The resulting blaze was quickly extinguished and officials said efforts were under way to get shipments back to normal from Iraq’s second city of Basra where fighting broke out on Tuesday.

It is the first time since 2004 the vital southern route, responsible for about three quarters of Iraq’s exports, has been disrupted. Officials had different views about how long it would take to restore supplies and the gravity of the incident.

U.S. crude rose by more than $1 to trade above $107 a barrel after news of the attack.

“This morning saboteurs blew up the pipeline transporting crude from Zubair 1 by placing bombs beneath it. The pipeline was severely damaged,” the SOC official said, speaking on condition of anonymity.

“Crude exports will be greatly affected because this is one of two main pipelines transporting crude to the southern terminals. We will lose about a third of crude exported through Basra,” he said.

A source at the Basra terminal later on Thursday said oil was flowing to the terminal at around 1.2 million barrels per day (bpd), down 300,000 bpd from average rates.

“The last figure I had for the oil pipeline from the Basra terminal is around 50,000 barrels per hour and the reason why it’s not more than that is because of the damage to the pipeline earlier this morning,” the source said.

Even if one of the main export pipelines was damaged, backup pipelines running from tanks at Zubair, Rumaila and Tuba oilfields can be used to keep supplies flowing to Basra, an oil official said.

VARYING DAMAGE ASSESSMENTS

Officials in Baghdad said the pipeline was not severely damaged and output was returning to previous levels.

“Instructions are being given to restore pumping to normal levels. This was a minor incident,” one official said.

But engineers on the ground in the south said fighting was hampering efforts to repair the line and they were waiting until Friday morning to begin work. It could then take up to three days to carry out repairs.

Reuters could not independently verify where the damage took place. But the SOC official said the attack occurred seven kilometers south of Basra on a major pipeline connecting the Rumaila and other southern oilfields to the Basra terminal.

There was no immediate claim of responsibility.

Officials in Baghdad said a branch leading from the Bazargan oilfield to the pipeline, rather than the main export link itself, had been affected.

Iraq’s government relies heavily on oil exports for revenue, and had managed to sustain the flow from Basra even as a violent insurgency targeted the country’s oil installations elsewhere.

In the north, persistent sabotage and technical problems had reduced exports to a trickle since the U.S.-led invasion in 2003, but flows have improved greatly since last summer.

Exports of around 430,000 bpd of Kirkuk crude continued to flow through a pipeline to Turkey, a shipping source said on Thursday.