A suspected suicide bomber carries a backpack on a street in Negombo, Sri Lanka April 21, 2019 in this still image taken from a CCTV handout footage of Easter Sunday attacks released on April 23, 2019. It is unclear if anybody was hurt in the explosion.
Sri Lanka's Health Minister Rajitha Senaratne said a local radical group the National Towheed Jamaat was responsible for the attacks and investigations were ongoing to find out whether they had foreign links.
The Easter attacks, which have claimed more than 290 lives and injured a further 500, targeted several churches including St. Anthony's, as well as three hotels, a zoo, and a private residence.
Pompeo has spoken to the Sri Lankan Prime Minister Ranil Wickremesinghe Monday morning and stated that the United States is offering "all possible assistance".
The ministry of foreign affairs has said it believes 35 foreign nationals are also among the dead, including at least eight British citizens - two with joint USA citizenship.
But cabinet spokesperson Rajitha Senaratne said the attacks were carried out by a local militant group named National Thowfeek Jamaath - with the help of an worldwide network.
Police said that 40 people were now under arrest over the suicide bomb attacks - the worst atrocity since Sri Lanka's civil war ended a decade ago.
Greta Thunberg at London climate protest: 'We will never stop fighting'
Climate change activists are seen during an Extinction Rebellion protest at Oxford Circus in London, Britain April 19, 2019. She added: "I think it's wrong that this is happening, this existential crisis, and that people have to do these things".
Sri Lankan and USA officials say they suspect the co-ordinated series of bombings was launched by Islamic extremists, though no group has claimed responsibility.
The CCTV camera inside the Church also recorded the Sri Lanka bomber entering the church after touching a small child in front of the church.
Islamic State has claimed responsibility for the massacre.
Fortunately, no injuries have been reported from this latest explosion. "Information to help identify individuals linked to these attacks could come from anywhere in the world world, which is where Interpol's global network and databases can prove vital".
"Terrorists may attack with little or no warning", the updated travel warning reads.
Police said 87 bomb detonators were found at the city's main bus station, while an explosive went off near a church where scores were killed on Sunday when bomb squad officials were trying to defuse it.
GP Sally Bradley and her husband Bill Harrop, a retired firefighter from Manchester decorated for his role in the aftermath of the 1996 IRA attack, died in the Cinnamon Grand Hotel bombing.