Embattled British pop star Tulisa Contostavlos has sparked rumours of an N-Dubz comeback after she was photographed posing with her reunited bandmates. The group went on hiatus in 2011 to allow Contostavlos, along with rappers Dappy and Fazer, to launch solo careers, but they are now said to be plotting a comeback after a picture posted on Instagram.com showed the trio together again. The snap was taken by Contostavlos' personal assistant and has sparked rumours the band is working on new music. Contostavlos has endured a tough time during her hiatus from N-Dubz - her solo career was branded a flop after her album limped into the U.K. charts at number 35, and she was dropped from her role as a judge on Britain's The X Factor. The star has also been embroiled in a police investigation and charged with supplying drugs following an undercover sting operation by a U.K. newspaper. Her bandmate and cousin Dappy has also been in the headlines for all the wrong reasons during his time off - earlier this year (13), he was convicted of assault stemming from a brawl at a gas station.