BEIRUT (AP) — Warplanes carried out air raids Sunday on several parts of northern Syria as a rebel spokesman warned that continued violations of a fragile cease-fire could jeopardize a planned resumption of U.N.-brokered peace talks. [...] Syria's state news agency said militants fired shells into government-held areas in the coastal province of Latakia from their bases near the Turkish border. Opposition activists and state media also reported clashes between troops and members of the Islamic State group mostly in the northern province of Aleppo. [...] Sunday, Riad Hijab, who heads the High Negotiations Committee, an umbrella for opposition and rebel factions, said in a statement directed to U.N.