Foreign Minister Feridun Sinirlioğlu called U.S. Secretary of State John Kerry Friday night to discuss Russian airstrikes on Turkmen villages in Syria.Turkish officials have been closely watching recent developments in Turkmen villages in the Bayırbucak Turkmen area in northwestern Syria, which is in the immediate vicinity of Turkey's Yayladağ border crossing.The Foreign Ministry summoned Russia's ambassador to Ankara over the bombings and requested that Russia promptly end the operation. It also sent a letter to the U.N. Security Council regarding the issue.The late night phone conversation in which the two top diplomats evaluated the situation after the offensive on the Turkmen region came on orders from Prime Minister Ahmet Davutoğlu.Ankara also sent a letter to the term president of the U.N. Security Council to demand that the issue be handled immediately.Sources added that Davutoğlu was informed by Chief of General Staff Hulusi Akar by phone regarding the latest situation in the region.At the Prime Ministry, National Intelligence Organization (MİT) Chief Hakan Fidan also briefed the Davutoğlu on the issue. Ankara had requested that Russia promptly end this operation, Foreign Ministry spokesman Tanju Bilgiç said on Friday, adding: "Our warnings and request have also been communicated to the Russian deputy foreign minister and special presidential representative for the Middle East, Mihail Bogdanov.""If any attack is mounted against civilians on Turkey's border, even with cluster munitions shelling, so as to draw the people living there toward Turkey and lead to a further refugee flow, all involved will be held responsible," Davutoğlu told the media in Istanbul on Friday.Almost 40,000 Syrian Turkmens fled from their homes to safer villages near the Turkish border Saturday following attacks by Syrian and Russian forces.A number of Turkmens also entered Turkey at the Yayladağı border crossing in southeastern Hatay province. The Disaster and Emergency Management Authority (AFAD), the Turkish Red Crescent and other humanitarian aid organizations began sending humanitarian aid including tents, food and mattresses to displaced Turkmens.A mobile bakery in Yayladağı also started producing bread to be delivered to Turkmens fleeing to safer villages near the Turkish border. Muhammed Komurcu, a Syrian Turkmen Association official, told Anadolu Agency that the number of internally displaced people has doubled. Mokhtar Fatih Mohamed, head of a Turkmen doctors group in the Bayır Bucak region, told Anadolu Agency on Friday that the Turkmen-majority area is about to fall to regime forces, which may cause 15,000 Turkmen to flee to Turkey.Turkmens are a Turkic ethnic group based with minority populations in Syria and Iraq where they live alongside large Arab and Kurdish populations. The Turkmen community in these countries includes both Sunnis and Shiites and shares cultural ties with Turks.Syria's devastating civil war, now in its fifth year, has left at least 250,000 people dead, according to the U.N.