The Sri Lankan government has declared a curfew with immediate effect, and shut down all major social media and messaging services.
"A curfew will be imposed until things settle down," junior defence minister Ruwan Wijewardene told reporters in Colombo.
Government officials said Facebook and WhatsApp have been blocked to prevent misinformation and rumours.
Nearly 140 people have been killed and more than 400 people wounded after eight bomb blasts ripped through churches and hotels in the island nation on Sunday.
US threatens to strike Iran's Kharg Island oil network after military targets 'obliterated'
US embassy in Baghdad hit in missile attack, security sources say
Four killed in Russian air attack on Kyiv region, officials say
Nigerian army kills 18 terrorists, arrests 37 suspects
North Korea fires missiles towards sea during US, South Korea drills
