Justin Bieber shirtless

 He may look a good deal younger than his 19 years, but Justin Bieber is continuing to make an effort to hone a more manly image.

The pint sized singer posted new shirtless photographs of himself on his Instagram account showing his burgeoning six pack is coming along nicely.

The pictures also display Justin's growing number of tattoos, which include Roman numerals, a crown, a tiger, an angel and a koi fish.

A second shot features the star in another shirtless pose, with the shots appearing to have been taken after his concert in Denver on Sunday.