Jonathan Black, the son of Conrad Black, has been arrested and charged after allegedly breaking his girlfriend's wrist, CBC News has learned.

Black, 38, was arrested on Thursday afternoon and charged with assault causing bodily harm.

He spent the night in custody at a Toronto police station.

The altercation occurred Thursday morning, CBC News has learned.

Black has also been charged with mischief. According to court documents, Black "wilfully" damaged his girlfriend's cellphone.

Black was remanded in police custody and will spend the weekend in a detention centre, his lawyer said. He will remain in custody until Monday at the earliest, when he can appear in court again.

In 2011, Black pleaded guilty to criminally harassing a former girlfriend. In 2008, he was fined $2,000 after leaving the scene of a traffic accident he caused in downtown Toronto.

Conrad Black, the former newspaper mogul and member of Britain's House of Lords, has three children. Jonathan Black is the eldest of the three.