The shock move was announced by telecoms operator Emtel, which said it was ordered late Thursday by the information and communication technologies authority to block access to all social media platforms.

The blockage is due to last until Nov 11 – a day after the election.

Emtel said the order referred to “illegal postings that may impact national security and public safety”.

It follows a scandal that broke out earlier this month when secret recordings of phone calls by politicians, journalists, members of civil society and even foreign diplomats were leaked online.

There was no immediate comment from the government on the social media ban.

“It’s shocking, revolting, and unacceptable. It’s a sign of panic,” said Paul Berenger, one of the leaders of the opposition Alliance for Change coalition.

“We are dealing with people who are dangerous to the country. Lawyers are working on what can be done legally. We will move very quickly on the legal and political level.”

Prime Minister Pravind Kumar Jugnauth is seeking re-election as head of the Militant Socialist Movement.

He inherited the premiership on the death of his father in 2017 and secured a victory for his coalition in polls two years later.

“This is the last desperate act of a regime in disarray,” said Nando Bodha, head of opposition grouping Linion Reform.

“It attacks head-on the fundamental rights of citizens guaranteed by the constitution, including freedom of expression,” he added, calling for an intervention by the election commission to ensure the polls are “free and fair”.