Justin Bieber - Troubled Justin Bieber Cancels Portugal Show

The pop superstar completed a four-night residency at London's O2 Arena on Friday (08Mar13) after a tumultuous trip to Britain which included a headline-grabbing bust-up with a photographer just hours before his final show.

Bieber's Believe tour is now heading to Europe, but he has axed his Tuesday night (12Mar13) show in Lisbon, Portugal.

His gig at the Pavilhao Atlantico venue on Monday (11Mar13) will go ahead as planned and local reports suggest the second concert there was axed due to slow ticket sales.

A statement posted on the venue's website reads, "Due to unforeseen circumstances, Justin Bieber was forced to cancel the second performance in Portugal, March 12. The Canadian singer is eager to play for the Portuguese fans on March 11."

Ticketholders have been offered refunds.

The Baby hitmaker's wild antics dominated headlines during his trip to the U.K. and culminated in his hospitalisation on Thursday (07Mar13) to treat breathing difficulties.

He was involved a birthday bust-up with bouncers at a London nightclub, as well the foul-mouthed altercation with a photographer on Friday (08Mar13). Bieber, 19, also angered many fans by leaving them waiting for several hours at the first gig of his residency at the city's O2 Arena, promoting a furious response from parents who were forced to take their young children home before the show had even started.