Singer jokes about 'breakdown'

Justin Bieber has flaunted his muscular chest in new shirtless selfies while blasting critics of his sexy snaps.

The Instagram photos, taken in a gym mirror, show the 19-year-old revealing his abs and yellow boxer shorts in low-slung tracksuit bottoms

In the captions the singer defends his decision to upload the gratuitous pictures and responds to rumours that he is heading towards a breakdown.

“Uh oh @justinbieber is losing it taking shirtless pics in the mirror” – funny people,‘ he writes.

Breaking news worldwide @justinbieber just posted 2 shirtless pictures he must be going crazy” -funny people #forthefansanyways #dontbecreepin :p.

The teen star, who recently shadow-boxed while visiting Anne Frank‘s house in Amsterdam, often uses Instagram to defend his increasingly strange behaviour. 

‘I’m tired of all the countless lies in the press right now,’ he told fans in March.

Saying I’m going to rehab and how my family is disappointed in me. My family is beyond proud.’

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