A three-day protest at a strategic oil refinery staged by former rebels demanding medical treatment has cost Libya about $30 million, a senior official said on Monday. "The demonstration has cost the country at least $30 million until now," outgoing deputy oil minister Omar al-Shakmak told AFP in reference to the protest in the western city of Zawiyah. Shakmak said the losses were due to the interruption of operations at the refinery, which supplies both the domestic and international markets, and the suspension of exports from its port. About 150 war veterans are taking part in the sit-in, according to residents. They want to be treated for injuries suffered in the 2011 conflict that toppled dictator Moamer Kadhafi. "They want to be evacuated as quickly as possible," said Naima al-Hammi, who represents Zawiyah in the national assembly. "Some risk losing organs if they are not treated." Hammi said there had been a high-level meeting Sunday to address the issue, and that the authorities were working to obtain the necessary visas to transfer the most urgent cases to hospitals in Europe. But the protesters were refusing to budge until a solution was finalised. The demonstration has caused ripples in Tripoli, 50 kilometres (30 miles) east of Zawiyah, with long lines forming at petrol stations and contributing to monster traffic jams. But the distribution director for Libya's National Oil Corporation, Adnen Abdelmaula, sought to reassure the public, telling the official LANA news agency that fuel reserves can hold for more than two months. Established in 1976, the Zawiyah oil refinery was the first built by NOC. It supplies the west of the country, accounting for about 70 percent of domestic consumption. Libyans often seek medical treatment in other countries due to poor conditions at local hospitals. Government schemes that took former rebels for treatment abroad have been cut due to abuse, corruption and outrageous bills.