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By Feras Bosalum
TRIPOLI, March 31 (Reuters) - Libya has released three rebel fighters who had boarded a tanker loading oil at a rebel-held port before it was returned to Tripoli by the U.S. navy, an official said on Monday.
The attorney general ordered the release following comments by some lawmakers that this would help solve the blockage of oil ports by the rebels, Sadiq al-Sour, head of the attorney's investigations department, told Reuters.
The eastern rebels, who have seized three major ports to press for a greater share of oil revenue and regional autonomy, had demanded the release of the fighters before starting any talks about lifting the blockage.
Three weeks ago, the rebel militia managed to load crude onto the Morning Glory tanker at the Es Sider port, which is under their control. U.S. special forces later stormed the ship and returned it to Libya.
Sour said he regretted the release which had been made on political grounds. "These are people who committed crimes," he said. "Now justice is entering political conflicts."
The government and parliament had told the militia to negotiate an end to their port blockade or face a military offensive. The rebels had demanded the release of their men, the tanker returned and the threat of an army offensive dropped.
Tripoli has been trying to end the port blockage because the government badly needs oil revenue. The three ports previously accounted for more than 600,000 barrels a day of exports, adding to the effects of oilfield closures in the west.
The port blockade is one of many challenges facing the government which has failed to secure the country three years after the fall of Muammar Gaddafi.
Former anti-Gaddafi rebels and militias refuse to surrender their weapons and often use force or control of oil facilities to make demands on a state whose army is still in training with Western governments.
Those governments, which backed NATO air strikes to help the 2011 anti-Gaddafi revolt, are pressing the factions to reach a political settlement.
Libya's oil production has fallen to a trickle due to the port seizures and protests at major oil fields. (Reporting by Feras Bosalum; Writing by Ulf Laessing, editing by David Evans)