Barcelona: Hundreds of thousands of Catalan separatists rallied in downtown Barcelona on Sunday to demand the release of high-profile secessionist leaders being held in pre-trial detention.

Protesters waved Catalan separatist flags behind a huge banner that read "for rights and liberties, for democracy and unity, we want them back home!"

The demonstration was organised by two pro-independence grassroots groups, the National Catalan Assembly and Omnium, whose presidents are among the nine separatists in prison awaiting trial for their roles in last year's failed breakaway bid by the north-eastern Spanish region.