UNITED NATIONS ? The U.N. Security Council on Friday called on Libya's warring parties to urgently de-escalate fighting and commit to a cease-fire, and it condemned a deadly attack on a detention center for migrants near the capital Tripoli. The U.N.'s most powerful body also called on the parties to rapidly return to U.N.-mediated political talks. The council press statement was the first approved by all 15 members since self-styled Libyan National Army leader, Field Marshal Khalifa Hifter, launched a military offensive on April 4 aimed at taking Tripoli, though it had previously issued weaker press quot;elements.quot; The statement was spurred by Tuesday night's airstrike on the...