The Islamic State group on Tuesday claimed a series of bombings that killed more than 320 people in Sri Lanka, after the government blamed local extremists for the blasts.
"Those that carried out the attack that targeted members of the US-led coalition and Christians in Sri Lanka the day before yesterday are Islamic State group fighters," said a statement released by IS propaganda agency Amaq.
Sunday's bombings targeting churches and high-end hotels are among the deadliest such attacks worldwide since the 2001 strikes on the United States.
The Sri Lankan government on Tuesday blamed the Islamist National Thowheeth Jama'ath (NTJ) group for the blasts, saying they were carried out in retaliation for last month's attacks on two mosques in New Zealand.
The presidency said there was intelligence that "international terror groups" were backing Sri Lankan extremists.
Police sources told AFP Tuesday that two Muslim brothers -- sons of a wealthy Colombo spice trader -- were among the perpetrators of the attacks.
They blew themselves up as guests queued for breakfast at the Shangri-La and Cinnamon Grand hotels in the capital, the source said.
The pair were key members of the NTJ, which the government has previously blamed for defacing Buddhist statues, according to an investigation officer.
Tuesday's claim by IS comes one month after a Kurdish-led Syrian force announced victory over the IS proto-state, after routing jihadists from their last holdout in east Syria with backing from a US-led coalition.
Even after losing their last scrap of territory in the eastern Syrian village of Baghouz, the jihadists retain a global network of recruits and have claimed attacks in Iraq, Syria and beyond.
On Sunday, IS claimed responsibility for an attack that killed 10 people and trapped around 2,000 for hours inside the communications ministry in the Afghan capital Kabul the previous day.
Beirut, Lebanon | AFP