Turkey's government survived an attempted coup, as President Recep Tayyip Erdogan promised to cleanse the military of the plotters, and reports of clashes continued into Saturday morning.
"They will pay a very high price for this betrayal," Erdogan said in a televised address, blaming the coup on US-based religious leader Fethullah Gulen.
Gulen condemned the putsch, saying "governments should be won through a process of free and fair elections, not force."
Around 120 people were arrested so far in connection with the insurrection, Prime Minister Binali Yildirim was quoted as saying by Anadolu news agency report. News footage showed soldiers in custody.
"Things are getting better with each passing moment," he was quoted as saying Saturday morning.
Former military legal advisor Muharrem Kose was also identified as a key figure behind the insurrection, news agency Anadolu reported. Yildirim said earlier that army head Hulusi Akar remained in control of the military throughout and was not part of the coup.
Aerial dogfights and bombings, military blockades and clashes between mobs and armed forces were reported across Turkey overnight. A helicopter used by soldiers backing the coup was shot down by a military jet over Ankara, broadcaster NTV reported.
At least 17 people were killed, reports said.
A large explosion was heard in central Istanbul shortly before Erdogan's television appearance, apparently close to Taksim Square. There were also reports of multiple explosions at the parliament building in Ankara.
Several military commanders and all four major political parties - including three in opposition - rejected the coup, blaming a small group within the military, according to NTV, Hurriyet newspaper and a government official.
Gulen, blamed by Erdogan, was once the president's ally in trying to bring his mildly Islamic-rooted Justice and Development Party to power. However, since a split several years ago, Erdogan's forces have moved actively to dislodge Gulenists from power in Turkey.
"It was the parallel organization," Erdogan said Saturday of the coup attempt, referring to Gulen's ongoing influence in the civil service and politics.
Earlier, wtnesses reported crowds chanting "Allah Akhbar" (Praise Allah) in the streets of Istanbul. Prayers were being called out from mosques in Istanbul, hours before scheduled morning prayers.
State broadcaster TRT went off air for several hours, as did CNN Turk after reporting a raid by soldiers. Both had resumed broadcasting early Saturday.
Soldiers reportedly took over the airport in Istanbul and stopped flights. Several international air carriers including Lufthansa, Aeroflot and KLM recalled flights to Turkey.
Armed forces also shut down several key bridges.
The US White House said "all parties in Turkey should support the democratically elected government of Turkey, show restraint, and avoid any violence or bloodshed."
Similar calls came from EU foreign policy chief Federica Mogherini and Iran. NATO called for "calm and restraint" and respect for "Turkey's democratic institutions."
Fars reported that two border crossings between Iran and Turkey had been shut down and that President Hassan Rowhani was planning a crisis meeting on the situation in Turkey.