At least three people have been killed after gunmen launched an attack on Iraq's Akkas gas field.
The culprits of Monday's attack also abducted two workers before burning their camp in the remote western desert, Reuters news agency reported.
"Gunmen in vehicles attacked the headquarters of a local company hired by KOGAS [Korea Gas Company ] to do work in the field," said Farhan Ftaikhan, mayor of al-Qaim, a nearby town. "They killed an engineer and two workers and kidnapped two more. Before they left they set fire to vehicles and offices."
Akkas, operated by KOGAS in Anbar province near the Syrian border, is still not producing gas.
No group claimed responsibility for the late-night assault, but security officials said the Islamic State of Iraq, the local wing of al-Qaeda, is regaining ground in the remote hills, caves and villages along the Syrian border.
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The group is allegedly linked to Sunni fighters battling the forces of Syrian President Bashar al-Assad across the border. Officials say it has been invigorated by arms, fighters and support flowing to rebels in Syria.
The Akkas strike was the second large attack on Monday.
Earlier, a suicide bomber driving a fuel tanker packed with explosives hit a local government compound and killed at least nine people in the northern city of Tikrit.
Attacks on Iraq's energy sector are less common, and usually hit pipelines, as country builds up its oil production to more than three million barrels per day after signing massive deals with foreign companies to develop its reserves.
Iraq, which holds the world's tenth largest gas reserves, has said the priority for the Akkas field would be domestic
consumption once it starts production.
Baghdad signed a final deal for the field, which has reserves of 5.6 trillion cubic feet, in October 2011 after months of delays because of disagreements between the central government and Anbar provincial officials over terms.