Is Justin Bieber Losing it? The Teen Heartthrob Posts Twitter Rant Before Stepping Out In Bizarre Gas Mask

Bieber Fever / Splash News/ Craig Harris/WENNBieber Fever / Splash News/ Craig Harris/WENN

Justin Bieber has been getting up to some pretty wild antics while in the UK and raised even more eyebrows when he stepped out wearing a bizarre gas mark last night.

The Canadian singer was spotted wearing the odd head piece as he headed to Japanese restaurant Nobu in Knightsbridge with his entourage.

Is Justin Bieber Losing it? The Teen Heartthrob Posts Twitter Rant Before Stepping Out In Bizarre Gas Mask Is Justin Bieber Losing it? The Teen Heartthrob Posts Twitter Rant Before Stepping Out In Bizarre Gas Mask

Justin wore a gas mask whilst heading to dinner in Knightsbridge (Bieber Fever / Splash News)

Bieber was is no mood to be photographed as he pulled his cream hooded jumper and a baseball cap over the mask to cover up as much of his head as possible before.  After his meal, Bieber  made his made to 45 Park Lane, with his mask in tow, to continue a "chilled" evening with friends.

The star's weird behaviour comes after he took to Twitter to slam critics in a lengthy tirade in which he justified his partying, asked not to be judged and said he would remain positive despite the negative press attention of late.

"So yeah I will continue being me. i will continue to serve, to perform, to care, to love, to smile, to dance, to play, to sing... " Tweeted Bieber, adding: "but know this...im only judged by one power, and i serve him."

Is Justin Bieber Losing it? The Teen Heartthrob Posts Twitter Rant Before Stepping Out In Bizarre Gas Mask Is Justin Bieber Losing it? The Teen Heartthrob Posts Twitter Rant Before Stepping Out In Bizarre Gas Mask

Bieber has been raising eyebrows with his wild antics in the UK (Craig Harris/WENN)

Continuing: "I understand it is part of the job to be judged...but judge me on the facts, judge me on the music, and be careful of the judgement u pass.

"Or any girl i stand next to is my girl or that i dont care, or that i dont feel, or that a 19 year old going to a club in europe is wild..."

Since landing in the UK, the teen singer has made constant headlines over his colourful love life in which he has been seen with several mystery woman, with some allegedly returning to his hotel.

Added to that, the popstar was also forced to carry out damage control after arriving two hours to his 02 concert last week, which insiders have claimed was down to Bieber throwing a mega tantrum.

Do you think Bieber is losing it?

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