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.
Israeli fire kills three people in Gaza as truce deal staggers
Cuban forces kill 4 exiles who attacked from Florida speedboat
Hong Kong court overturns China critic Lai's fraud conviction in rare legal victory
Hillary Clinton to testify in congressional Epstein probe
Death toll from Brazil floods rises to 46, 21 people still missing
