BBC's PM Modi Series In Supreme Court: Why Use 'Emergency Powers' To Block?

The row over the blocking of the BBC docuseries on PM Modi has reached the Supreme Court. The Centre has now been asked to explain the move to block 'India: The Modi Question'. The court has issued a notice to the government to which it has to reply within three weeks. The petitioners have challenged the use of emergency powers to block the documentary and remove links from social media. The court acted on a petition by veteran journalist N Ram, activist-lawyer Prashant Bhushan, and Trinamool Congress MP Mahua Moitra, asking that the Centre be stopped from censoring the documentary. A separate petition by lawyer ML Sharma calling the ban on the two-part documentary "malafide, arbitrary, and unconstitutional" and said the Centre never formally publicised the blocking order. So what are these provisions being used to block the docuseries and what's the justification for it.