The organizer of the Istanbul airport massacreis a well-known terrorist who served as a top lieutenant in the ISIS war ministry, a U.S. official said.
Akhmed Chatayev, from Russia's North Caucasus region, directed the three suicide bombers who killed 44 people Tuesday, said rep Michael McCaul, chairman of the House Committee on Homeland Security.
Turkish media reported that a man nicknamed "Akhmed One-Arm" organized the attack.
While his whereabouts are unclear, his ties to jihadist activities are well documented, McCaul said.
"He's ... probably the No. 1 enemy in the Northern Caucus region of Russia. He's traveled to Syria on many occasions and became one of the top lieutenants for the minister of war for ISIS operations," he told CNN's Brianna Keilar.
Suspect on U.S. list of terrorists
At least 230 others were injured when the trio stormed Istanbul's Ataturk Airport and opened fire with rifles before detonating bombs. Two of the men targeted the international terminal building, and the third one gunned down people at the parking lot.
"We believe he (Chatayev) coordinated with the three suicide bombers in Istanbul to conduct this attack during the season of Ramadan," McCaul said.
Last year, the U.S. Treasury added Chatayev to its list of terrorists, saying he was planing attacks against U.S. and Turkish facilities. The United Nations has said he directly commands 130 militants.
Officials believe the three attackers -- identified by state media as from Russia, Uzbekistan and Kyrgyzstan -- entered Turkey a month ago from Syria's ISIS stronghold of Raqqa.
They brought with them suicide vests, bombs and a deadly plan from ISIS leadership.
Growing trend
McCaul said his information on Chatayev came from Turkish intelligence. Turkish officials have not confirmed his involvement to CNN.
The allegation mirrors a growing trend of battle-hardened fighters from Russia and former Soviet republics joining ISIS in recent years.
Chechnya produced many fighters following the 1990s wars that pitted Russian forces against Chechen separatists.
Russians deployed brutal tactics in Chechnya, which radicalized the insurgents and moved them in an Islamist and militant direction, CNN national security analyst Peter Bergen said.
In October, Russian President Vladimir Putin said between 5,000 to 7,000 fighters from Russiaand the former Soviet republics are in Syria.
"Ask anybody inside ISIS or who's fought ISIS. People from the former Soviet Union tend to be the most ... willing to die," said CNN contributor Michael Weiss, author of "ISIS: Inside the Army of Terror."
ISIS leadership involved
Chatayev's alleged connection may not be a surprise.
Turkish officials have strong evidence that ISIS leadership was involved in the planning of the Istanbul terrorist attack, a senior government source told CNN.
And the attacks appear organized.
The three terrorists rented an apartment in the Fatih district of Istanbul after they arrived from Syria a month ago, officials said.
After the airport attack, one of the terrorists left behind his passport, according to a Turkish government source.
Turkish police visited the Fatih area and showed neighbors video and photographs of three men they believe carried out the attack, residents said.
One man who owns a real estate agency said one of the men in the picture had lived in his apartment. He said he was shocked the man was a suspect in the attacks.
No claim of responsibility
While no one has claimed responsibility for the airport assault, Weiss said the nationalities of the terrorists point to ISIS involvement.
"One of the toughest battalions in ISIS is called the Uzbek battalion," he said. "These were the guys who were essentially on the front lines guarding Falluja, the city they just lost in Iraq."
The tactic used in the airport attack -- shooting, and then detonating explosives -- is called "inghimasi," and it's being used more frequently by terrorists.
"The 'inghimasi,' their (modus operandi) on the ground in Syria and Iraq, is to shoot up checkpoints and then they actually -- some of these guys actually run up to the enemy and hug them before detonating the bomb to take them out with themselves. So in a sense, the ultimate Kamikaze warrior," Weiss said.
ISIS also has a history of airport attacks. It claimed responsibility for dual suicide bombings at the main airport in Brussels in March. At least 10 people died in those blasts.
The victims
Those killed came from all over the world, but most were Turkish, including 10 airport employees, TAV Airports CEO Sani Sener said.
Saudi Arabia's foreign ministry said six Saudis were killed and dozens more wounded.
Other fatalities included nationals from Saudi Arabia, Iraq, Tunisia, China, Iran, Ukraine, Jordan and Uzbekistan.
One U.S. citizen suffered minor injuries, Homeland Security Secretary Jeh Johnson said.
Authorities have detained 22 people in the attack, including three foreign nationals.
Credit: CNN
