Condolences and condemnations of terrorism are pouring in from around the world in the aftermath of the deadly attack on the airport in Istanbul, Turkey.
The White House quickly condemned what it called a "heinous terrorist attack" at Istanbul's Ataturk airport Tuesday.
Presumptive Republican U.S. presidential nominee Donald Trump said the assault was "so sad." Insisting in a tweet: "We must do everything possible to keep this horrible terrorism outside the United States." Trump has called for a ban on all Muslims coming to the United States, but more recently has scaled back his proposal to those coming from countries wracked with terrorism.
Democratic presidential candidate Hillary Clinton expressed sympathy for the Turkish people and called for the U.S. to "deepen" its "cooperation" with allies in the Middle East and Europe to take on the threat of terrorism. "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," she said in a statement.
Forensic experts work outside Turkey's largest airport, Istanbul Ataturk, following a blast in Turkey, June 28, 2016.
U.N. Secretary-General Ban Ki-moon also called for stepped-up cooperation in the fight against terrorism. The U.N. chief "stands firmly by Turkey as it confronts this threat and stresses the need to intensify regional and international efforts to combat terrorism and violent extremism," his spokesman said in a statement.
European Union leaders expressed their solidarity with Turkey.
"I want to say to all of the Turkish people that we consider ourselves united with them in the fight against terror," German Chancellor Angela Merkel said.
French President Francois Hollande said, "As I unfortunately did before in other circumstances also about Turkey, I also want to strongly condemn the attack and make sure we can know exactly who the perpetrators are so that, together, we can do anything possible to do to fight against terrorism, especially in this region."
Belgian Prime Minister Charles Michel tweeted from a closed-door meeting in Brussels, "Despicable terror attack. Stand together with people of Turkey."
U.S. Secretary of State John Kerry said officials are still trying to figure out who attacked the airport and what exactly happened. "This is daily fare, and that's why I say the first challenge we need to face is countering nonstate, violent actors," he said.
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.