BEIRUT, Lebanon — Terrorists attacked sites in France, Tunisia and Kuwait on Friday, leaving a bloody toll on three continents and prompting new concerns about the spreading influence of jihadists.
In France, attackers stormed an American-owned industrial chemical plant near Lyon, decapitated one person and tried unsuccessfully to blow up the factory.
In Tunisia, gunmen opened fire at a beach resort, killing at least 27 people, officials said. At least one of the attackers was killed by security forces.
And the Islamic State claimed responsibility for a suicide bombing in one of the largest Shiite mosques in Kuwait City during Friday prayers. The bomb filled the hall with smoke and left dead and wounded scattered on the carpet, according to witnesses and videos posted online. Local news reports said at least 24 people had been killed and wounded in the assault, which was extraordinary for Kuwait and appeared to be a deliberate attempt to incite strife between Shiites and Sunnis.
In a message circulating on social media, the Islamic State called the suicide bomber “one of the knights of the Sunni people.”
There was no immediate indication that the attacks had been coordinated. But the three strikes came at roughly the same time, and just days after the Islamic State, the militant group also known as ISIS or ISIL, called for such operations during the Muslim holy month of Ramadan.
“It appears to be an effort to launch and inspire a wave of attacks across three continents, reminiscent of Al Qaeda’s simultaneous multiple attacks of the past,” said Bruce O. Riedel, a former C.I.A. officer who is a counterterrorism expert at the Brookings Institution in Washington.
“The Kuwait operation is especially dangerous, as this is ISIS’ first operation in a gulf state,” Mr. Riedel said in an email. “The others will be deeply alarmed.”
While investigations continued in each of the countries, the quick succession of the attacks raised the possibility that the Islamic State, which has seized control of territory in Iraq and Syria, has successfully inspired sympathizers to plan and carry out attacks in their own countries.
“Muslims, embark and hasten toward jihad,” said the Islamic State’s spokesman, Abu Mohammed al-Adnani, in an audio message released this week. “O mujahedeen everywhere, rush and go to make Ramadan a month of disasters for the infidels.”
United States intelligence and counterterrorism officials were scrambling on Friday to assess the connections, if any, between the attacks in France, Kuwait and Tunisia. Officials said that if the assessment found that the attacks were linked, officials would seek to determine whether the Islamic State had actively directed, coordinated or inspired them.
The assault in Kuwait was particularly worrisome. A tiny, wealthy oil exporter, Kuwait has been largely insulated from the mayhem in the region, and open tensions between Sunnis and Shiites are not common.
But the assault resembled others launched by ISIS recently on Shiite mosques in neighboring Saudi Arabia, prompting many to believe that ISIS is seeking to incite a sectarian war between Sunnis and Shiites.
Some Kuwaitis said that with sectarian tensions rising across the region, it was only a matter of time before they reached Kuwait.
“Ever since I heard about Qatif and the Shiite mosques there, I just had this feeling that we were next,” said Bodour Behbehani, a Shiite graduate student in Kuwait City, recalling a mosque bombing last month near the city of Qatif in Saudi Arabia.
“This is something that was planned,” she said. “It was not just one guy who decided to put on a suicide belt and go in there.”