Ankara, March 14 () - Turkish President Recep Tayyip Erdoğan and Prime Minister Ahmet Davutoğlu have reiterated their resolve to fight terrorism after a car bomb killed dozens of people just weeks after a similar attack.   In a statement after the bombing which killed at least 37 people in the capital city, Erdoğan said terrorist organizations were targeting civilians because they were losing their struggle against security forces.   “Our state will never give up using its right of self-defense in the face of all kinds of terror threats. All of our security forces, with its soldiers, police and village guards, have been conducting a determined struggle against terror organizations at the cost of their lives” Erdoğan said in a written statement, noting that Turkey had become a target for terrorist acts because of growing regional instability in recent years.   “Our people should not worry, the struggle against terrorism will for certain end in success and terrorism will be brought to its knees” he said.   No group immediately claimed responsibility for the March 13 killings, yet Davutoğlu said investigators were following up on solid leads.   “We have concrete information on the terrorist group behind the attack” Davutoğlu said in a written statement. “We will soon have results from the inquiry, and will make them public” he said, adding that the attack targeted all of Turkey.   “Our country has been targeted by multidimensional terror attacks in a thorny and instable region. As has the been the case earlier, from now on too, the Republic of Turkey will conduct its struggle against terror with a great determination for the sake of our nation’s unity and serenity and it will punish treacherous circles that aim at our country in the heaviest way” Davutoğlu said.