Ja Rule is one of the US's biggest rap stars

The hip-hop star, whose real name is Jeffrey Atkins, turned himself in after an incident at a Toronto nightclub on 5 June, police said.

Mr Atkins, a 28-year-old New Yorker with two Grammy nominations, is charged with assault causing bodily harm.

He was also held earlier this month in New York City for marijuana possession, but the charge was dropped.

As the flagship artist for the Murder Inc label, later renamed The Inc, Ja Rule's career exploded in 1999 with the hit single Holla, Holla.

He later mellowed his hardcore style to do a series of 2002 pop-friendly duets with stars Jennifer Lopez and Ashanti , and has collaborated with Case and Jay-Z.

His 2001 album Pain is Love was nominated for the 2002 Grammy for best rap album, while single Livin' It Up was up for best rap/sung collaboration. Always On Time had a nomination in 2003 for best rap/sung collaboration.

He also has a minor acting career, most notably a role in 2001 in The Fast and the Furious.