Bruno Mars lands first U.S. number one album

Bruno Mars has scored his first number one album in America thanks to a massive Amazon.com price drop.

Fans took advantage of a $1.99 online offer and snapped up copies of Unorthodox Jukebox, propelling the album to number one on the Billboard 200, just ahead of Amok, the new release from Radiohead star Thom Yorke and Flea's supergroup Atoms for Peace.

Last week's top album, Mumford & Sons' Babel, falls to three, Macklemore & Ryan Lewis' The Heist climbs to four and Hillsong United's Zion debuts at five.

Meanwhile, Baauer's viral hit Harlem Shake has landed a third week at the top of the Hot 100 pop charts, one spot ahead of Macklemore & Ryan Lewis' Thrift Shop, which becomes the first track to score more than 300,000 digital sales for eight consecutive weeks. Fun. managed seven weeks of high sales last year (12) with their anthem We Are Young.