Yemeni tribesmen launched a fresh attack on a key pipeline overnight, interrupting the flow of oil and forcing troops to deploy as technicians were blocked from repairing the installation, officials said Thursday. The attack in the Sarwah area of Marib province, 170 kilometres (105 miles) east of the capital Sanaa, was the second time the pipeline has been targeted in less than a fortnight. An official said armed members of tribes also cut off the road leading to the damaged pipeline to prevent technical teams from reaching the site and carrying out repair works. Yemeni army troops were deployed to reopen the road, he said on condition of anonymity. Tribesmen from Marib have frequently attacked the pipeline to pressure the central government in Sanaa to release several of their arrested comrades. On June 13, a soldier was killed in clashes with the tribesmen after they attacked the 320-kilometre long pipeline. Electricity Minister Saleh Sumai has blamed loyalists of former president Ali Abdullah Saleh, who was forced to step down early last year after being in power since 1978, for carrying out the attacks to destabilise the country. In December, the army launched an offensive against tribesmen suspected of being behind these attacks, sparking clashes in which 17 people were killed. Yemen, an impoverished Arabian Peninsula country, produces 300,000 barrels of oil per day and relies on its exports to fund the state budget at a time when the political crisis and rising insecurity have brought its economy to the brink of collapse. Lost oil production due to pipeline attacks in the east cost the government more than $1 billion (746 million euros) in 2012, as exports fell by 4.5 percent, official figures say.