TORONTO » Justin Bieber was charged today with assault for allegedly hitting a Toronto limousine driver several times in the back of the head last month, just hours after his attorney entered a separate not guilty plea in Florida to drunken-driving and other charges.

Bieber turned himself in to a Toronto police station, arriving amid a crush of media and screaming fans. He was charged with one count of assault and is scheduled to appear in court in Toronto on March 10.

Police allege Bieber was one of six people who were picked up by a limousine from a nightclub in the early morning hours of Dec. 30, and there was an altercation while en route to a hotel.

Police said during the altercation one of the passengers hit the limo driver in the back of the head several times.

"The driver stopped the limousine, exited the vehicle and called police," a statement said. "The man who struck him left the scene before police arrived."

Howard Weitzman, Bieber’s attorney in California, said his client is innocent and declined to comment on the allegations against Bieber or any potential defense, saying it was now a matter for the court to handle.

Weitzman said he expects the case to be treated as a summary offense, which is the equivalent of a misdemeanor in the United States. "The Toronto Police Service requested that Justin Bieber appear in Toronto today to face an allegation of assault relating to an incident on December 29, 2013. We anticipate that this matter will be treated as a summary offense, the equivalent of a misdemeanor in the United States," he said in a statement.

Brian Greenspan, Bieber’s Canadian attorney, did not immediately return a message seeking comment.

Toronto police said in late December they were looking into allegations that a member of Bieber’s entourage assaulted a limo driver who was ferrying the Canadian pop star and several others. Police said at the time it was unclear whether Bieber was involved. Bieber emerged from a black SUV wearing a winter coat and a backwards ball cap before being led through a throng of police and reporters. Many waited for his arrival for more than an hour in freezing temperatures. He spent about an hour and a half in the police station before leaving through a back exit.

It was yet another sign of the crazy lifestyle that has taken over Bieber’s image.

Earlier today, Bieber pleaded not guilty in Florida to charges of driving under the influence after driving nearly twice the speed limit on a Miami Beach street. He also pleaded not guilty to resisting arrest and driving with an expired license.

Court records show that Bieber’s attorney filed a written plea in Miami-Dade County. Bieber already has an arraignment set for Feb. 14, but Florida law doesn’t require the 19-year-old pop star to be present.

Bieber and R&B singer Khalil Amir Sharieff were arrested last week in Miami Beach during what police described as an illegal street drag race between a Lamborghini and a Ferrari. Neither has been charged with drag racing, which is a crime in Florida.

The Canadian pop star lately has drawn more attention for his brushes with the law than for his music. His arrival at the Toronto police station was no different — the singer debuted a music video for his song "Confident" this afternoon, just as news of his expected arrest was breaking.

Bieber remains under investigation for felony vandalism in Los Angeles County over an egg-tossing episode that damaged his neighbor’s home. Detectives searched his home on Jan. 14, and prosecutors have sought additional information before determining whether to pursue charges.

The cases have overshadowed the recent release of his latest album. Its reception has been far from the chart-topping success Bieber had after he debuted in 2009, with multiple platinum albums.

Last year, Bieber made headlines for everything from clashing with a paparazzo to fainting at a show to being photographed smoking marijuana. The paparazzo is suing Bieber for assault and battery.

German authorities charged him thousands of dollars after he abandoned a pet monkey that they seized from him for failing to have proper vaccination papers.

The singer also had to apologize to Bill Clinton after cursing the former president and spraying his photo with cleaning fluid in a New York City restaurant kitchen.

Bieber was discovered through a YouTube video of him performing, and his career has been guided by a pair of music industry heavyweights, singer Usher and manager Scooter Braun. He has been nominated for two Grammy Awards for his 2010 full-length album debut "My World 2.0," but his popularity has waned.

Braun tweeted this evening, "i ask people to be kind and hope for the best in people. not assume the worst. Thanks."

Jon Bollock, a 14-year-old fan waiting for Bieber to arrive outside the Toronto police station, said he wanted to see Bieber but said "it’s pretty embarrassing for Canada."

Associated Press writers Curt Anderson in Miami, Anthony McCartney in Los Angeles and Charmaine Noronha in Toronto contributed.