Canadian-born singer Justin Bieber's My World Tour has been doing exceptionally well, according to reports.

Everything's been cool. Everything's been great, said DJ Tay James, Bieber's tour DJ, in an interview with MTV News, Absolutely ridiculous. I've been with him since his second show and just to see him do shows with 300 people to us doing [shows with] 50,000, it's crazy. I'm just happy to be in the position that I am. That's like my little brother.

Bieber's bassist, Alex Suarez, said that he was amazed not only by the size of the crowd but also by its enthusiasm.

Beiber's fans have flooded his concerts, welcoming him with open arms at each and every city he has performed in. What else could such a young artist, with so brief a history in the industry, ask for?

Bieber also surprised his fans in Rio de Janeiro, when his girlfriend and fellow singer, Selena Gomez appeared on stage, to perform briefly alongside him, STV reported.

Gomez performed her hit song Who Says and was joined by Bieber, towards the end of the song. That must have been a delightful treat to fans of both Bieber and Gomez.

Check out pictures of the concert.

Justin Bieber My World Tour
Canadian pop singer Justin Bieber performs during his "My World Tour" concert at Morumbi stadium in Sao Paulo, October 8, 2011. REUTERS/Nacho Doce
Justin Bieber My World Tour
Canadian pop singer Justin Bieber performs during his "My World Tour" concert at Morumbi stadium in Sao Paulo, October 8, 2011. REUTERS/Nacho Doce
Justin Bieber My World Tour
Fans of Canadian pop singer Justin Bieber cry during a concert at Morumbi stadium in Sao Paulo October 8, 2011. REUTERS/Nacho Doce
Justin Bieber My World Tour
Fans hold a cardboard cut-out of Canadian pop singer Justin Bieber while camping outside the Morumbi stadium before his upcoming concert in Sao Paulo October 7, 2011. Bieber will perform two concerts in Sao Paulo as part of his "My World Tour." REUTERS/Nacho Doce
Justin Bieber My World Tour
Canadian pop singer Justin Bieber greets his fans from the balcony of his hotel in Mexico City October 2, 2011. Bieber is performing two concerts in Mexico City as part of his "My World Tour." REUTERS/Stringer
Justin Bieber My World Tour
Canadian pop singer Justin Bieber performs during his "My World Tour" concert at the Foro Sol in Mexico City October 1, 2011. REUTERS/Henry Romero
Justin Bieber My World Tour
Canadian pop singer Justin Bieber greets his fans from the balcony of his hotel before leaving for his first "My World Tour" concert at the Foro Sol in Mexico City October 1, 2011. REUTERS/Stringer
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