Turkish rescue services gather outside Istanbul's Ataturk airport, Tuesday, June 28. | AP Photo Trump on Istanbul attack: 'Will the world ever realize what is going on?'

Reacting to the bombing at Istanbul's Ataturk airport that killed at least 28 people and injured 60 others, Donald Trump on Tuesday tweeted that the United States "must do everything possible" to prevent similar acts of terrorism in the United States.

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

Advertisement Yet another terrorist attack, this time in Turkey. Will

the world ever realize what is going on? So sad. — Donald J. Trump (@realDonaldTrump) June 28, 2016

Minutes later, Trump tweeted: "We must do everything possible to keep this horrible terrorism outside the United States."

We must do everything possible to keep this horrible terrorism outside the United States. — Donald J. Trump (@realDonaldTrump) June 28, 2016

"Our prayers are with the families of those killed and injured in Istanbul. The whole world is stunned and horrified," Trump said in a statement subsequently emailed to reporters. "The terrorist threat has never been greater. Our enemies are brutal and ruthless and will do anything to murder those who do not bend to their will. We must take steps now to protect America from terrorists, and do everything in our power to improve our security to keep America safe."

Istanbul Governor Vasip Şahin said that three suicide bombers targeted the airport, and Turkish justice minister Bekir Bozdag said one attacker opening fire before detonating explosives.

U.S. Secretary of State John Kerry, speaking from Aspen, Colorado, did not leap to conclusions about the motive or the perpetrators in addressing the attack, the latest in a string of bombings to hit Turkey in recent months.

"We are still collecting information and trying to ascertain what happened and who did it and I won’t comment further on it except to say this is daily fare and that’s why I say the first challenge we need to face is countering non-state violent actors for a host of reasons," Kerry said from the 2016 Aspen Ideas Festival.

The Istanbul attack comes after Turkey resumed normal diplomatic relations with Israel, with which ties had become strained in the wake of Israel's fatal 2010 raid on a Turkish flotilla in support of Palestinians in Gaza.

Tyler Pager contributed to this report.