By NICHOLAS PAPHITISATHENS, Greece (AP) â¿¿ For the second time in less than two weeks, the Greek government invoked rarely used emergency laws to order strikers back to work Tuesday â¿¿ in a move designed to end a seamen's walkout that has left islands without ferry services and supplies for six days. The decision by conservative Prime Minister Antonis Samaras to declare ferry crews under civil mobilization came after their unions voted to extend the strike until early Friday. Seamen who refuse to comply risk arrest and jail time of up to five years â¿¿ although a union leader said workers would try to defy the order. Samaras' three-party coalition government is facing a strong backlash from unions over new austerity policies forced upon it by international creditors, whose bailout loans are shielding debt-heavy Greece from bankruptcy. The country's main unions have called a general strike for Feb. 20. Merchant Marine Minister Costas Mousouroulis said the government did what it could to address seamen's demands for payment of salaries more than six months in arrears and the signing of collective work contracts with ferry companies. "Unfortunately, arteriosclerotic and petty political views prevailed, not allowing (the end of the strike) so that our islands could regain their only means of communication with each other and the mainland," Mousouroulis said. Samaras' government had previously hinted heavily that it would mobilize the seamen unless they stopped the strike. The rarely-invoked order was also issued last month to end a protracted walkout by Athens underground rail workers. The Merchant Marine Ministry said ferry schedules could resume later Tuesday, depending on how fast strikers are served their mobilization papers. But seamen's union leader Yiannis Halas urged ferry crews to resist. "(The mobilization) will solve none of our problems," he told a protest gathering of about 1,500 seamen and supporters in the capital's port of Piraeus, Greece's largest. "We ask the crews to stay away from their ships and stay here. Courage and strength to all of us."