Terrorists launched horrific attacks across three continents Friday, killing dozens of people just days after ISIS urged supporters to unleash "a month of disaster" during the Muslim holy period of Ramadan.
A man was decapitated in an apparent Islamist attack on a U.S.-owned gas factory in southeastern France, while 25 worshipers were killed and 200 wounded during Friday prayers at a Shi'ite mosque in Kuwait.
In Tunisia, gunmen sparked panic at a beach resort, opening fire and killing at least 37 people — mostly foreigners.
While ISIS claimed responsibility for the attack in Kuwait, there were no immediate claims of responsibility for the other assaults.
The Pentagon was trying to determine whether the attacks were coordinated or coincidental, spokesman Col. Steve Warren said, according to Reuters. The U.S. State Department said there was no evidence so far that that was the case.
Governments around the world condemned the attacks and went into high alert. Britain's Prime Minister David Cameron called an emergency security meeting of officials in London, while France stepped up security at key sites and held a similar summit of defense chiefs at the Elysee in Paris.
The White House described the attacks as "heinous," adding: "We stand with these nations as they respond to attacks on their soil.
"We are resolute and united in our shared effort to fight the scourge of terrorism," it added in a statement.
I am sickened by the attacks in Tunisia, France and Kuwait. Our countries stand together in combatting the horrors of terrorism.— David Cameron (@David_Cameron) June 26, 2015
Global terror attacks 'sophisticated,' mar first week of Ramadan 1:26
While there was little to suggest any co-ordination between the atrocities, experts noted that they came shortly after ISIS spokesman Abu Mohammad al-Adnani called on supporters to step up their activities.
"O mujahidin everywhere, rush and move to make Ramadan a month of disaster," he said Tuesday, encouraging Islamists to "embark and hasten towards jihad."
Charlie Winter, of London's Quilliam Foundation, said: "Whether or not there is any link at all between these attacks, they are likely to be inspired by the same ideals."
Olivier Guitta, security analyst with GlobalStrat, said the Tunisia attack was "a major PR coup for ISIS," even if the group was not directly responsible.
Friday's attacks showed that ISIS has the ability to inspire attacks even by supporters with no direct connection, he added.
"They have followers who are not members of ISIS that are actually listening to [messages], being inspired by them and then going on a whim and doing their terrorist actions," he said.
In the Tunisia beach massacre, vacationers — including Western tourists — fled for cover after gunmen opened fire.