TEHRAN (Tasnim) � Secretary of Iran's Supreme National Security Council (SNSC) Ali Shamkhani expressed deep concern over a recent attempted coup in neighboring Turkey and said Tehran is closely monitoring the developments in the neighboring country.

�We are following the events in Turkey warily and carefully,� Shamkhani said in a statement in Saturday morning, referring to an attempted Turkish military coup that was crumbled in the early hours of Saturday.

The Iranian official further emphasized that Tehran considers instability in Turkey as a threat to the people�s security and tranquility.

"All of the land and air borders with Turkey are under full control, and comprehensive surveillance is underway in the areas," he added.

The coup in Turkey appeared to crumble in the early hours of Saturday after crowds answered President Tayyip Erdogan's call to take to the streets to support him.

Erdogan, who had been holidaying on the southwest coast when the coup was launched by a faction in the armed forces, flew into Istanbul before dawn on Saturday and was shown on TV appearing among a crowd of supporters outside Ataturk Airport.

The uprising was an "act of treason", and those responsible would pay a heavy price, he later told reporters at a hastily arranged news conference. Arrests of officers were under way, and it would go higher up the ranks, culminating in the cleansing of the military, he said.

The coup began with warplanes and helicopters roaring over Ankara and troops moving in to seal off the bridges over the Bosphorus Strait that links Europe and Asia in Istanbul.

Authorities had shut the strait to tanker traffic. A helicopter open fire in Ankara. Anadolu said military helicopters had fired on the headquarters of the intelligence agency.

Airports were shut and access to internet social media sites was cut off in the first hours of the coup attempt.

Soldiers took control of TRT state television, which announced a countrywide curfew and martial law. An announcer read a statement on the orders of the military that accused the government of eroding the democratic and secular rule of law. Turkey would be run by a "peace council" that would ensure the safety of the population, the statement said.

TRT went off the air shortly afterwards. It resumed broadcasting in the early hours of Saturday.

Anadolu said the chief of Turkey's military staff was among people taken "hostage" in the capital Ankara but Prime Minister Yildirim later said he was back in control.

The coup had appeared strong early on Friday evening.

Istanbul's Ataturk Airport has reopened and news channels have begun broadcasting again, after being temporarily shut down by soldiers earlier in the night.

By Tasnim News Agency