TMZ posted some pictures that allegedly show JUSTIN BIEBER smoking pot in a California hotel room.

He hasn't admitted to it, but after the pictures hit the web, he Tweeted, quote, "Everyday growing and learning. trying to be better. u get knocked down, u get up. Back on tour tomorrow. Ready to see u all smile. Time to do what I'm supposed to be doing . . . performing."

Click the pic for the rest of the images!