Sri Lanka is reeling after a series of explosions ripped through churches and hotels across the nation, killing more 290 people and wounding at least 500.
Among the 290 killed in Sri Lanka's horrific Easter Sunday attacks were two Australians. Another two were also injured.
Prime Minister Scott Morrison announced from Melbourne on Monday that the two Australians killed were members of the same family and had been living in Sri Lanka at the time of Sunday's attacks, which saw eight bomb blasts rip through high-end hotels and churches holding Easter services.
"We deeply regret these deaths and we extend our deepest and most sincere sympathies to the family," he said.
"Two Australians have lost their lives in this terrible massacre. My heart is full of grief for them and their families. I'm sure all Australians' are."
He added that the two injured Australians - a woman in her mid-50s and another in her mid-to-late-20s - were receiving consular assistance.
"One was treated for shrapnel wounds and the other has been treated for a broken leg," Mr Morrison said.
87 bomb detonators found at Colombo bus station
Police on Monday said they had found 87 bomb detonators at a Colombo bus station.
A statement said police found the detonators at the Bastian Mawatha Private bus stand, 12 of them scattered on the ground and another 75 in a garbage dump nearby.
On Monday, an investigator said seven suicide bombers took part in the attacks.
Two of the suicide bombers blew themselves up at the luxury Shangri-La Hotel on Colombo’s seafront, said Ariyananda Welianga, a senior official at the government’s forensic division. The others targeted three churches and two other hotels.
A fourth hotel and a house in a suburb of the capital Colombo were also targeted, but it was not immediately clear how those attacks were carried out.
“Still the investigations are going on,” Welianga said.
There was no claim of responsibility for the Easter Sunday attacks, which mainly took place during church services or when hotel guests were sitting down for breakfast buffets.
The world mourns Sri Lanka victims
By Monday, the death toll from the attacks had risen to 290, with about 500 people also wounded.
Police spokesman Ruwan Gunasekera declined to give a breakdown of those killed and wounded at each of the three churches and four hotels hit on Sunday, attacks that marked the most significant violence since a bloody civil war ended 10 years ago.
Sri Lankan police had on Monday arrested more than 20 people in connection with bomb blasts on churches and hotels, officials said.
Authorities have not made public details on those held after Sunday's attacks. But a police source told AFP that 13 of the arrested men are from the same radical group.
At least two of the eight attacks were carried out by suicide bombers, according to police and other sources, and three police were killed when another suicide bomber detonated explosives during a raid on a house where suspects were.
The apparently coordinated attacks were the deadliest to hit the country in the decade since the end of a bloody civil war that killed up to 100,000 people and evoked painful memories for many Sri Lankans.
There was no immediate claim of responsibility, but the government said investigators would look into whether the attackers had "overseas links".
The government also imposed a nationwide curfew - which was later lifted - and curbed social media access to prevent "wrong information" from spreading in the country of 21 million people.
The powerful blasts – six in quick succession and then two more hours later - injured hundreds.
At least two of them involved suicide bombers, including one who lined up at a hotel breakfast buffet before unleashing carnage.
By late Sunday, police had already confirmed the toll to be at 207 dead and 450 people injured.
Police said 35 foreigners were among the dead, including American, British, Chinese, Dutch, Danish, Australian, Indian and Portuguese citizens.
New Delhi said three Indians were killed, while Washington and London also confirmed an unspecified number of their nationals were among the dead.
Among the churches targeted was the historic St Anthony's Shrine, a Catholic church in Colombo, where the blast blew out much of the roof.
Bodies lay on the ground of the church, covered in patterned scarves and white sheets, some of them stained with blood.
Shattered roof tiles and shards of glass littered the floor, along with chunks of plaster blasted from the walls by the explosion.
Documents seen by AFP show that Sri Lanka's police chief Pujuth Jayasundara issued an intelligence alert to top officers 10 days ago, warning that suicide bombers planned to hit "prominent churches".
"A foreign intelligence agency has reported that the NTJ (National Thowheeth Jama'ath) is planning to carry out suicide attacks targeting prominent churches as well as the Indian high commission in Colombo," the alert said.
The NTJ is a radical Muslim group in Sri Lanka that was linked last year to the vandalisation of Buddhist statues.
Prime Minister Ranil Wickremesinghe acknowledged that "information was there" about possible attacks and that an investigation would look into "why adequate precautions were not taken".
Two Chinese nationals were injured, the country's embassy in Sri Lanka said, according to Beijing's official Xinhua news agency.
Who did it?
There was no immediate claim of responsibility, and Prime Minister Ranil Wickremesinghe declined to identify any suspected perpetrators.
At least 20 people have been arrested in connection with the attacks, police said, and investigators would look into whether the attackers had "overseas links".
The island nation has suffered deadly militant attacks for years, especially by ethnic Tamil militants during a decades-long civil war that ended in 2009 when Sri Lankan forces crushed the insurgency.
In recent years, there have been clashes between the majority Sinhalese Buddhist community and minority Muslims, and in March last year the government imposed a 12-day state of emergency to quell anti-Muslim riots.
Christian groups have also complained of increased harassment from hardline Buddhist groups.
And, according to documents seen by AFP, the country's police chief warned top officers 10 days ago of possible suicide bomb attacks on churches and the Indian high commission by the National Thowheeth Jama'ath (NTJ), a radical Muslim group in Sri Lanka. He cited reports by a "foreign intelligence agency", according to the documents.
AFP reports the Sri Lankan government believes NTJ was behind the deadly suicide bomb attacks that killed nearly 300 people, government spokesman Rajitha Senaratne said on Monday.
Mr Senaratne, who is also a cabinet minister, added that the government was investigating whether the group had "international support".
"We don't see that only a small organisation in this country can do all that," he said.
"We are now investigating the international support for them, and their other links, how they produced the suicide bombers here, and how they produced bombs like this."
A police source on Monday told AFP that all 24 people in custody in connection with the attacks belong to an "extremist" group, but did not specify further.
How did Sri Lanka react?
Wickremesinghe urged people to "hold our unity as Sri Lankans" and pledged to "wipe out this menace once and for all."
The Archbishop of Colombo, Malcolm Ranjith, described the attackers as "animals" and called on authorities to "punish them mercilessly".
The government beefed up security and imposed an immediate and indefinite curfew across the country. It also put in place a "temporary" ban on social media platforms "in order to prevent incorrect and wrong information being spread".
Security at Colombo's airport was also enhanced, according to Sri Lankan Airlines, which advised its passengers to arrive four hours before their flights.
It added that passengers with passports and tickets will be able to reach the airport during the curfew.
Embassies in Sri Lanka have warned their citizens to shelter in place.
Australian Tamils appalled by attacks
The Australian Tamil Congress (ATC) has released a statement condemning the attacks carried out on churches and hotels in Sri Lanka on Easter Sunday.
"The ATC is saddened at the loss of innocent lives and stands in solidarity with the victims and their loved ones," the statement read.
"Sri Lanka has a long history of religious extremism and perpetrators of religious violence have been known to act with impunity.
"As recent as 27 March 2019 the UN High Commissioner for Human Rights, Ms Bachelet, while underlining the importance of accountability to the people of Sri Lanka, told the UN Human Rights Council that “continuing impunity risks fuelling communal or inter-ethnic violence, and instability”.
"The ATC calls on Sri Lankan authorities to take act responsibly and genuinely to bring justice to victims, including local and foreign nationals who have perished.
"The ATC further calls on Sri Lanka to refrain from knee jerk reactions, ensure the human rights of all in the island are respected and prevent any further acts of oppression targeting any particular community which can perpetuate the further divide between communities."