The ousted Sri Lankanprime minister's party urged Facebook to safeguard the identity of its supporters on the social media platform, fearing information sharing with what it calls the country's "illegal" government can lead to a crackdown against the users.
In a letter to Facebook chief Mark Zuckerberg, the United National Party said such information could be used against the users "in ways which are legally prohibited".
Party spokesman Piyasena Dissanayaka said Sunday that Facebook blocked its official page ahead of a public rally on Thursday but restored it on Saturday.
"It is very likely that officials from the current illegal administration ... may ask Facebook for information on selected Sri Lankan users of Facebook that should rightfully be private," said the letter, sent on Thursday.
"Such requests may include information on named individuals, geo locations and other identification details of users who view and post on these pages," the letter said.
"It is vital this information be safeguarded as the current illegal administration will most likely use these in ways which are legally prohibited."