Coldplay are set to kick off their North American tour after treating fans to a series of free concerts.

They've recently staged free gigs in London and Barcelona, ending with New York City's Madison Square Garden.

The Brit band recently achieved their first-ever number one single with Viva La Vida - released as a download single only.

The last time Coldplay threatened to snatch the top spot in the singles charts was back in 2005, when critics and fans alike were left dumbfounded after Crazy Frog's Axel F beat the group to it.

Meanwhile, the band's fourth studio album, Viva La Vida Or Death And All His Friends, is also at number one.

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