Turkish Official: At Least 36 Dead After Suicide Bombers Blow Themselves Up At Istanbul Airport

ISTANBUL (CBSNewYork/AP) -- Three suspected Islamic State group suicide bombers targeted the international terminal of Istanbul's Ataturk airport Tuesday, killing at least 36 people and wounding many others, Turkish officials said.

Turkish Prime Minister Binali Yildirim said 36 were dead and Justice Minister Bekir Bozdag said 147 were wounded. Another senior government official told The Associated Press the death toll could climb much higher.

The senior official, who spoke on condition of anonymity in line with government protocol, at first said close to 50 people had already died, but later said that the figure was expected to rise to close to 50.

Yildirim said three suicide bombers were responsible for the attack and all initial indications suggest the Islamic State group was behind it.

He said the attackers arrived at the airport in a taxi and blew themselves up after opening fire.

Asked whether a fourth attacker might have escaped, Yildirim said authorities have no such assessment but are considering every possibility.

PHOTOS: Dozens Killed In Istanbul Attack

The victims included some foreigners, he said, adding that many of the wounded have minor injuries but others are more badly hurt.

Another Turkish official said two of the attackers detonated explosives at the entrance of the international arrivals terminal after police fired at them, while the third blew himself up in the parking lot.

The official, who also spoke on condition of anonymity in line with government protocol and cited interior ministry information, said none of the attackers managed to get past security checks at the terminal's entrance.

Turkish airports have security checks at both the entrance of terminal buildings and then later before entry to departure gates.

A U.S. intelligence source told CBS News that the three attackers had grenades, automatic weapons and suicide vests. There is currently no claim of responsibility, but the source said this has all the hallmarks of an ISIS attack.

CBS2's Tony Aiello reported that the attack occurred around 10 p.m.

Video purportedly shows the explosion at the airport.

Another video appears to show a second attacker who falls, drops his weapon, and detonates his vest several moments later.

According to Turkish newspaper Haberturk, one of the suspects threw four grenades toward the security check.

Turkish President Recep Tayyip Erdogan condemned the attacks, saying it "shows that terrorism strikes with no regard to faith and values."

He called on the international community to take a firm stand against terrorism and vowed to keep up Turkey's struggle against terror groups.

"Turkey has the power, determination and capacity to continue the fight against terrorism until the end," Erdogan said.

Eye witness Ercan Ceyhan told CNN-Turk that he saw some 30 ambulances enter the airport.

Hundreds of passengers were spilling out of the airport with their suitcases in hand or stacked onto trolleys. Others were sitting on the grass, their bodies lit by the flashing lights of ambulances and police cars.

Two South African tourists, Paul and Susie Roos from Cape Town, were at the airport and due to fly home at the time of the explosions and were shaken by what they witnessed.

"We came up from the arrivals to the departures, up the escalator when we heard these shots going off," Paul Roos said. "There was this guy going roaming around, he was dressed in black and he had a hand gun."

Hevin Zini, 12, had just arrived from Duesseldorf, Germany, with her family and was in tears from the shock.

"There was blood on the ground," she told The Associated Press. "Everything was blown up to bits... if we had arrived two minutes earlier, it could have been us."

South African Judy Favish, who spent two days in Istanbul as a layover on her way home from Dublin, had just checked in when she heard an explosion followed by gunfire and a loud bang.

She says she hid under the counter for some time.

Favish says passengers were ushered to a cafeteria at the basement level where they were kept for more than an hour before being allowed outside.

Recent Fordham University graduate Adam Keally said he tried to help the injured.

"One guy had holes in his back from shrapnel from glass," Keally said. "That's what I was holding, you know."

Laurence Cameron just got off his flight when the explosions occurred.

"I'd just stepped off the plane and as I walked around the corner to where the visas are issued, there's this massive crowd of screaming people," Cameron said. "Just pure panic, people falling over themselves."

Video shows people huddled in a store following the explosions.

The private DHA news agency said the wounded, among them police officers, were being transferred to Bakirkoy State Hospital.

CBS News' senior national security analyst Juan Zarate told CBSN that this attack is similar to those conducted by ISIS.

"The initial reaction is it is potentially Kurdish groups who have been amplifying their attacks...on the other hand, this also follows an Islamic State MO," Zarate said.

Zarate also said that American intelligence agencies are assessing what happened and whether other attacks are likely.

"Both to understand who the perps were here but also to understand whether there are other threats percolating or unfolding in the region," Zarate explained. "That's always a major concern that this isn't just a singular event, but could be one of several that could affect American interests."

The White House said President Barack Obama has been briefed about the attack.

Presumptive Republican presidential nominee Donald Trump took to Twitter to comment on the attack.

"Yet another terrorist attack, this time in Turkey. Will the world ever realize what is going on? So sad," Trump tweeted.

Trump then added, "We must do everything possible to keep this horrible terrorism outside the United States."

Presumptive Democratic presidential nominee Hillary Clinton said in a statement that "all Americans stand united with the people of Turkey."

"Today's attack in Istanbul only strengthens our resolve to defeat the forces of terrorism and radical jihadism around the world. And it reminds us that the United States cannot retreat. We must deepen our cooperation with our allies and partners in the Middle East and Europe to take on this threat," Clinton said.

Turkey has suffered several bombings in recent months linked to Kurdish or ISIS militants.

The bombings included two in Istanbul targeting tourists -- which the authorities have blamed on the Islamic State group.

The attacks have increased in scale and frequency, scaring off tourists and hurting the economy, which relies heavily on tourism revenues.

The U.S. State Department said they are trying to determine if Americans were among the victims.

The NYPD said they are following the events in Turkey closely and will adjust their deployment as needed.

Istanbul's Ataturk Airport was the 11th busiest airport in the world last year, with 61.8 million passengers, according to Airports Council International. It is also one of the fastest-growing airports in the world, seeing 9.2 percent more passengers last year than in 2014.

The largest carrier at the airport is Turkish Airlines, which operates a major hub there. Low-cost Turkish carrier Onur Air is the second-largest airline there.

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