Turkish police detained 11 foreigners on Friday suspected of belonging to an Islamic State cell linked to the attack on Istanbul's main airport, as authorities focused their investigation into a suspected Chechen mastermind.
The pro-government Yeni Safak newspaper has said the organizer of the attack, the deadliest in a series of suicide bombings in NATO-member Turkey this year, was suspected to be a man of Chechen origin called Akhmed Chatayev.
US Representative and House Committee on Homeland Security chairman Michael McCaul reiterated these suspicions on CNN Friday morning, saying Chatayev was behind the attack.
Forty-four people were killed in Tuesday's bombings and shootings, which targeted one of the world's busiest airports. Turkish government officials have said the three suspected attackers were Russian, Uzbek, and Kyrgyz nationals.
Chatayev is not a new name to authorities and agencies around the world. He is currently identified on a United Nations sanctions list as a leader in Islamic State responsible for training Russian-speaking militants.
The Chechen was also arrested in Bulgaria five years ago on a Russian extradition request but freed because he had refugee status in Austria, a Bulgarian judge told Reuters.
In 2012, Georgian officials said Chatayev had been wounded in a special forces operation against an unidentified group in the remote Lopota Gorge near the border with Dagestan. The group was believed to be made up of Russian Islamist insurgents fighting against Moscow's rule in the North Caucasus.
Chatayev, whose foot had to be amputated due to his injuries, was arrested on charges of weapons possession. He denied the allegations and said that he had been sent to the gorge as a negotiator at the request of Georgian officials. A Georgian court ordered Chatayev's release later that year and cleared him of all charges in January 2013.
Friday's dawn arrests by counter-terror police in the European side of Istanbul were just the latest this week, with 24 people detained so far in the investigation, state-run Anadolu Agency said. A police spokesman could not confirm the report.
Turkish officials have not given many details beyond confirming the attackers' nationalities, saying that forensic teams were struggling to identify the suicide bombers from their limited remains. Local media on the other hand was quick to report alleged details on the suspected attackers.
Daily newspaper Yeni Safak has said the Russian bomber was from Dagestan, which borders Chechnya, where Moscow has led two wars against separatists and Islamist militants since the Soviet Union collapsed in 1991. Turkey's Hurriyet newspaper named the Russian bomber as Osman Vadinov and said he had traveled to Turkey from Raqqa, the heart of Islamic State-controlled territory in Syria. The Russian interior ministry has said it was checking information about Vadinov.
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