By By SUZAN FRASER Associated PressANKARA, Turkey (AP) - Turkish investigators were close to identifying one of two suicide bombers in the country's deadliest attacks in years, the prime minister said Monday, adding that the Islamic State group was the "No. 1 priority" of the investigation.Ahmet Davutoglu also said in an interview with private NTV television that the evidence pointed to a "certain group" which he refused to identify.The rally on Saturday was organized by Turkish and Kurdish activists to call for increased democracy and an end to the renewed fighting between Turkey's security forces and the Kurdish rebels that has killed hundreds since July.On Monday, Yeni Safak, a newspaper close to the government, said authorities investigating the bombings were focusing on the Islamic State group, comparing DNA samples of the suspected bombers with those obtained from families of some 20 extremists they suspect could have carried out the attacks.No one has claimed responsibility, but the attack bears similarities to a suicide bombing that killed 33 Turkish and Kurdish peace activists near the town of Suruc bordering Syria in July.