700 Catalan mayors marched in Barcelona supporting upcoming independence referendum

A man carries a sign that reads "Spain for sale" next to a huge banner reading "Independence Now" during a rally on Catalonia's national day 'La Diada' in Barcelona, Spain, September 11, 2017. REUTERS/Susana Vera

More than 700 Catalan mayors have marched in Barcelona, the capital of Spain’s Catalonia region in support of an upcoming independence referendum.

Catalan regional president Carles Puigdemont and several other top officials also joined the rally.

The mayors are under investigation by Spain’s government for cooperating with the referendum which Madrid vehemently opposes.

Meanwhile, armed police have raided several newspaper offices and printing companies in Catalonia in recent days searching for voting papers, ballot boxes and leaflets.

Police managed to seize large sums of advertising material during the hunt.

On Thursday, Catalonia launched its official campaign for the vote due to be held on October the first. Madrid says the referendum is illegal.