Ankara - Turkey's state television TRT broadcast a statement on Friday it said was from the Turkish Armed Forces who declared martial law and a curfew throughout the country."A curfew has been imposed until a second order," TRT said from the statement signed by the "Council for Peace in the Homeland." President Recep Tayyip Erdogan on Friday night vowed that "coup plotters" would not succeed, calling on people to take to streets in his support after a military group announced a power grab."I certainly believe that coup plotters will not succeed," Erdogan told CNN Turk television, speaking on FaceTime via mobile phone in his first reaction to the move by the Turkish armed forces."I urge the Turkish people to convene at public squares and airports. I never believed in a power higher than the power of the people." Erdogan said he was still president and Turkey's commander in chief, promising that plotters would pay a "very heavy price." A presidential source said Erdogan was in a secure location as per government protocol. In Washington, a White House official said on Friday night that President Barack Obama had been briefed by aides on events in Turkey."The president's national security team has apprised him of the unfolding situation in Turkey," said National Security Council spokesperson Ned Price. "The president will continue to receive regular updates."Meanwhile, The Associated Press reported that Russian Foreign Minister Sergey Lavrov and other Russian officials had called on their countrymen in Turkey to stay indoors. Lavrov made the statement early on Saturday at a news conference with US Secretary of State John Kerry. However, Lavrov, who had been in lengthy talks with Kerry, said he had little information about what was taking place in Turkey.Russia's tourism authority issued a similar warning. Turkey had long been a popular vacation destination for Russians, but the numbers dropped sharply last year when Russia banned package tours to Turkey amid tensions over Turkey shooting down a Russian warplane and it was unclear how many Russians currently are in the country.