Exports of crude oil from northern Iraq have been suspended after a new bomb attack against a key pipeline, an Iraqi person familiar with the matter and a Middle East shipping agent said Tuesday, the second such interruption in less than a week.

Iraq normally exports an average of 300,000 to 350,000 barrels a day via the pipeline, which carries crude from the Kirkuk oil fields to the Turkish port of Ceyhan .

"The attackers blew up part of the pipeline using six bombs planted underneath the line," a person familiar with the matter told Dow Jones Newswires.

The attack took place around 1 a.m. local time Monday north of the al-Shurgat area north of Baiji, some 200 kilometers north of the capital,
Baghdad , he said.

A
Middle East shipping agent in the Mediterranean port of Ceyhan confirmed that the flow has been stopped since early Monday.

Last week the pipeline was cut in a similar location in order to smuggle the crude. Flows resumed Friday after the damaged section was repaired. It may take three days to repair the section of pipe that was destroyed in Monday's attack, the Iraqi person said.

Shipping agents said they managed to pump some 2.6 million barrels of oil between Friday and Monday before the new attack.

Three vessels are waiting in port in Ceyhan to load with
Kirkuk crude, the shipping agent said.

The Iraq-Turkey pipeline has frequently suffered attacks, sometimes inside
Turkey and on other occasions inside Iraq . The pipeline was idle for many years due to acts of sabotage after the U.S.-led invasion in 2003.