The family of Sugababes’ Amelle Berrabah recently feared the singer had been kidnapped. Berrabah simply “vanished” for several days after getting into a huge argument with bandmate Keisha Buchanan.

Amelle - whose recent collaboration with rapper Tinchy Stryder, “Never Leave You,” topped the UK singles chart - walked out on the band, missed several performances and failed to respond to calls from her management. She was eventually found by police in her London home after locking herself her away.

“She is deeply unhappy at the moment and is scared of Keisha. She still loves the band and the last thing she wants to do is quit. But the problem needs to be addressed because she feels she is being bullied,” a friend said. “Keisha will criticize her throughout the day and it has been going on for months. It has got worse since Amelle had the Tinchy Stryder single and featured big-time in the ‘Get Sexy’ video. Keisha is very dominating while Amelle is quite placid.”

The group - which also includes Heidi Range - is due to fly to the United States next week to film the video for their new single and Amelle has told a friend she will make the flight.

The Sugababes have a history of arguments within the band and Amelle is the fifth member of the trio. Heidi replaced original member Siobhan Donaghy, while Amelle was brought in after founding member Mutya Buena quit the girl group.