Justin Bieber's hamster has died.

The Canadian singer's beloved rodent Pac - which he gave away to a fan in December after his performance at the Atlanta Jingle Ball show - has passed away due to what is thought to have been a chronic renal failure or a low protein diet.

Super-fan Tori McClure told TMZ the cute Russian dwarf hamster began losing its hair and a visit to the vet was unable to save him. She buried the beloved rodent in her garden, insisting, ''it's very peaceful there''.

Writing on her Twitter page, Tori revealed Pac has gone to ''little hamster heaven'', adding: ''He was OUR baby & @justinbieber I still can't thank u enough (sic)''

The teen idol's followers sent Twitter into a meltdown when they heard the news, and got #RIPac trending worldwide

The 18-year-old girl promised, ''I will take care of him'' as Justin handed him over to her outside the concert venue last winter, after having owned him for just two months.

However, Animal rights group The California Hamster Association predicted the death of poor Pac at the time, and were far from impressed by the way the 19-year-old singer disposed of his unwanted animal.

They said: ''The moment that hamster was handed off to a screaming girl in a harsh, frenzied environment was likely the moment it gazed at the short path to its doom.''

Justin has yet to comment on the sad loss and is lying low after a tough week in London.

The 'Boyfriend' hitmaker angered his young fans by arriving almost two hours late for his concert at The O2 arena, before ending the week by getting involved in a heated exchange with a paparazzi photographer.