In Kuwait, a suicide bomber blew himself up in a packed Shi'ite mosque during Friday prayers, killing two dozen. And in Tunisia, a gunman opened fire at a popular tourist hotel, killing at least 37 people.
There is no evidence the three attacks were deliberately coordinated. But coming so close together on the same day in three countries on three different continents, they underscored the far-reaching and fast-growing influence of Islamist group Islamic State, western politicians said.
The ultra-radical group, which has claimed direct responsibility for the Kuwait attack, clearly now poses a threat far beyond its heartland in Syria and Iraq.
It urged its followers this week to escalate attacks against Christians, as well as Shi'ite and Sunni Muslims fighting with a U.S.-led coalition.
On June 23, Islamic State spokesman Abu Muhammad al-Adnani urged jihadists to turn the holy month of Ramadan into a time of "calamity for the infidels ... Shi'ites and apostate Muslims".
"Be keen to conquer in this holy month and to become exposed to martyrdom."
Pentagon spokesman Col. Steve Warren noted Islamic State had claimed responsibility for one attack and said the Pentagon was looking into "whether or not these various and far flung attacks were coordinated centrally or whether or not they were coincidental."
Even if they were not coordinated, two sources familiar with the thinking of U.S. intelligence agencies said, they were likely to have been inspired by Islamic State's call to jihad or, possibly, the one year anniversary on Monday of the group's declaration of an Islamic caliphate in Syria and Iraq.
Adam Schiff, the top Democrat on the U.S. House Permanent Select Committee on Intelligence, said the attacks made clear that Islamic State's "ability to inspire and radicalize followers is a global threat and no nation is beyond its insidious reach".
Peter Neumann, director of the International Centre for the Study of Radicalisation, based in London, said it was unlikely the attacks were directly coordinated.
"I don't think that they talked to each other, knew of each other, or that there was a central command that told them to do that," he said. "There is zero evidence that they were coordinated."
At the same time, the French attack, which Neumann likened to other lone wolf attacks in the past year including in Sydney, Ottawa and Copenhagen, could have been inspired by Islamic State.
"In the case of the French attack, it's exactly the kind of attack that Islamic State wants people to do on their own without any prior consultation, coordination or whatever."
In September last year, Neumann said, the Islamic State spokesman urged followers not to "wait for us to tell you what to do. From now on you have permission to just strike wherever you want, kill infidels wherever you find them, do whatever is within your capability, just act."
While Islamic State has claimed direct responsibility for only the Kuwait attack, one Islamic State fighter told Reuters that in a general sense the assaults in both Kuwait and Tunisia had the blessing of the Islamic State caliphate.
"The speech of (IS spokesman Abu Muhammad) al-Adnani, may God protect him, he ordered soldiers and Amirs to make the month of Ramadan, the month of conquests and so it will be."
(With additional reporting by Mariam Karouny in Beirut and David Alexander in Washington; Written by Simon Robinson; Edited by Philippa Fletcher)