For the second time in less than a month, protesters in southern Iraq have impeded staff from accessing the 80,000 bpd oil field.
Ahdab field still producing, officials say, though protesters using road and checkpoint blockages could create logistical obstacles that could shut in fields.
A tribal dispute over contracts burst into violence, with field employees caught in the crossfire.
Many Iraqi commanders fighting an ongoing IS insurgency say a prospective U.S. military withdrawal would deprive them of crucial training and capabilities.
Production and exports so far unaffected as some foreign oil workers evacuate, following the U.S. assassination of Qassim Soleimani and Abu Mahdi al-Mohandis.
The Nassiriya oil field and Dhi Qar refinery are operating again after the Oil Ministry took them offline temporarily to de-escalate protests.
Oil Ministry takes an 82,000 bpd field offline as de-escalation tactic in response to protests; overall production and exports unlikely to be affected nationwide.
The killing of an oil facilities policeman at a Khabbaz well comes as insurgent attacks are on the upswing.
Thousands of Islamic State militants are believed to be in the area, exploiting security gaps.
Protesters are confronting an unbridgeable gap between their demands and the government's action. Their rising frustration poses increasing risks to the oil sector.
