The official, speaking on condition of anonymity under company policy, said the order was for Facebook, Instagram, Viber and WhatsApp. Some of those networks appeared to be blocked in Colombo, the capital, while others worked sporadically and very slowly.
A very different situation when compared to other governments and dictatorships attempts to block social media platforms. Sri Lankan authorities appear to focusing the ban in particular areas with current unrest due to Buddhist extremist groups inciting violence and burning the homes of Sri Lankan muslims.
Source: Sri Lanka blocks social media as anti-Muslim rioting flares – ABC News