Pop stars Justin Bieber and Taylor Swift won the big prizes on Sunday at the Billboard Music Awards, which also honored legendary performers Madonna and Prince.

Bieber, who was named top male artist, performed at the show at the MGM Grand Garden Arena in Las Vegas. He also took home Billboard's first Milestone Award, chosen by fans, for musical innovation and ingenuity.

"I'm 19 years old. I think I'm doing a pretty good job," Bieber said. "It should really be about the music. This is not a gimmick. I'm an artist and I should be taken seriously. And all this other bull should not be spoken of."

The teen heartthrob did not elaborate on what exactly he meant, but in recent months he has been involved in several high-profile incidents ranging from driving offenses to reports of hard partying and drugs being found on his tour bus in Sweden.

Swift won the top award of the night, artist of the year. She thanked her fans by telling them, "You are the longest and best relationship I've ever had."

Pop diva Madonna was handed the award for top touring artist for her MDNA Tour, 2012's highest-grossing concert series.

Madonna strode on stage to accept the accolade from will.i.am, wearing black fishnet stockings, garters and a padlock choker.

The MDNA Tour grossed more than $305 million from 88 sold-out shows and attracted an audience of 2.2 million people.

Madonna acknowledged her fans, saying, "A showgirl needs her fans. Thank you for supporting me for three decades."

She also thanked her four children for being "incredibly supportive."

The Billboard Music Awards, hosted by 30 Rock actor Tracy Morgan, opened with Bruno Mars performing "Treasure."