Dramatic footage has emerged from China of the moment a 118-metre-tall building was demolished.<br /><br />The building had never been put into use for a day since it was completed in 1999.<br /><br />The video, captured in Xi'an, Shaanxi Province on Sunday morning, shows the building disappearing into ash and rubble within 15 seconds following the explosions.<br /><br />According to news reports, the 27-storey building is so far the highest that has been demolished in mainland China ever and it had never been used during its whole life.