Turkey is to investigate the possible negligence concerning Saturday\'s deadly bombings at the border town of Reyhanli, which is close to Syria, Prime Minister Recep Tayyip Erdogan said Tuesday. \"The Prime Ministry Inspection Board will work for investigating whether there is negligence here (in Reyhanli attacks), and who is responsible for the negligence,\" Erdogan told lawmakers at the parliament. \"The powers behind the attack and the sub-contractors used\" have been clarified to a very large extent, Erdogan said, adding that the attacks were carried by \"an organization within Turkey which is related to the Syrian regime\" and that the perpetrators were citizens of Turkey. Turkey would retaliate against the twin car bombings, \"sooner or later\" and \"proportionately,\" Erdogan said Monday, but adding that the government would not let Turkey to be dragged into the civil war in Syria. Turkey has arrested 13 Turkish citizens for their alleged involvement in the bombings, which killed at least 51 people and injured over 100 in Reyhanli, where thousands of Syrian refugees took shelter. Ankara has been quick to point its finger at Damascus after Saturday\'s blasts -- an unsurprising move as relations between the two former allies have soured especially after the outbreak of the Syrian crisis, which Turkey says has resulted in escalated violence in border areas. For its part, the Syrian government on Tuesday suggested forming a Turkish-Syrian team to probe the Reyhanli explosions. It also said the attacks were a direct result of the spread of terrorism in the region, blaming Ankara for the deterioration of security near the joint border as it let the area become strongholds and conduits for the terrorists.