Ed noted this earlier but I wanted to focus on it plus add some new information. Two days after the deadly suicide bomb attacks in Sri Lanka, ISIS has claimed responsibility for the attacks and has released photos and video of the men it claims were the bombers. From the NY Times:

The group’s news agency, Amaq, released a bulletin on Tuesday stating that the attacks were carried out by “Islamic State fighters.” The statement, which was disseminated on the group’s chat rooms on the app Telegram, also said that the bombings targeted Christians as well as citizens of countries belonging to the coalition fighting the Islamic State, also known as ISIS.

In a later news release, the Islamic State identified the seven suicide bombers by their noms de guerre, and specified which of them had gone to each of the churches that was bombed during what it called “the infidel holiday.”

Still later on Tuesday, Amaq published a video showing eight men — apparently the Sri Lanka attackers — pledging allegiance to Abu Bakr al-Baghdadi, the leader of ISIS whom they called “emir of the believers.” They hold their hands up, index fingers pointed skyward, in a gesture that the Islamic State has adopted to refer to belief in one God.

One or two of the bombers are believed to have fought in Syria, though no one is saying they fought with ISIS yet. Rukmini Callimachi who covers ISIS for the Times posted a thread about the claim of responsibility on Twitter. She argues that the planning for this attack would have to have been significant and that it’s likely dozens of people were involved:

10. Once you have so many people involved, you need good operational security to make sure word of the looming attack doesn’t get out. They weren’t perfect given that authorities were warned earlier this month. But a plot of this nature takes longer than a month to hatch

— Rukmini Callimachi (@rcallimachi) April 23, 2019

As mentioned above, ISIS released names, photos and a video of the men it claims carried out the attack:

15. And finally, ISIS has issued a video from the alleged attackers. It shows the same 8 men as in the still photo above. They hold their hands together and pledge allegiance to Abu Bak al-Baghdadi, calling him "emir al-mumineem," the emir of the believers: pic.twitter.com/kjmxfX1VWB

— Rukmini Callimachi (@rcallimachi) April 23, 2019

18. It also shows that the alleged attackers were steeped in ISIS lingo. They knew that attackers are supposed to pledge allegiance to the caliph of the Islamic State before an attack. They correctly went through the honorific and the long sequence of family names in their pledge pic.twitter.com/PNPnTVMLWq

— Rukmini Callimachi (@rcallimachi) April 23, 2019

Finally, she says it’s not clear if this was intended in response to the Christchurch, New Zealand attack last month as some Sri Lankan authorities have claimed. ISIS itself hasn’t claimed this was a revenge attack, but people who support the group are doing so:

21. That said in ISIS’ larger ecosystem online in the chatrooms used by their supporters, Christchurch has been invoked. See this poster bragging about how many more Christians were killed versus Muslims in NZ. Again this is put out by supporters / is not official ISIS propaganda pic.twitter.com/EqimsVDXRP

— Rukmini Callimachi (@rcallimachi) April 23, 2019

CNN reports another link between the attack and ISIS. The multiple warnings that Indian authorities provided to Sri Lanka prior to the attack came from the interrogation of an ISIS suspect:

The first warning came more than two weeks before the attacks. Sri Lankan officials were told on April 4 of a potential plot to launch suicide attacks against Christian churches and tourist spots, government spokesman Rajitha Senaratne told reporters on Monday. The warnings were repeated two days and two hours before the attacks, Senaratne said.

Dehli’s information came from the interrogation of an ISIS suspect, the Indian source told CNN. After being interrogated, the suspect gave investigators the name of a man he trained in Sri Lanka, who is associated with the local extremist group, the NTJ, the source said.

“While we were investigating ISIS cases, during the interrogation of an accused, he disclosed the name of a man, Zahran Hashim, who is one of the suicide bombers and is associated with NTJ,” said the intelligence source in India. “The suspect said that he played a role in his (Hashim’s) radicalization.”

CNN says a Sri Lankan memo it has seen identifies Hashim as the leader of National Tawheed Jamath. He is believed to have been the mastermind of this attack. According to captions of the pictures above, Hashim is the man in the center who does not have his face covered. A former police official tells CNN the failure to heed the clear and specific warnings about a pending attack constituted “criminally negligent” behavior by authorities.