A petition has been launched to encourage action to be taken against Chris Brown after he allegedly smoked marijuana on stage in Ghana.

The US singer performed in the country on March 6 but video footage from the gig appears to show Brown smoking a joint and then playing songs that reference getting "high".

Ghanaian youth activist Jonathan Osei-Owusu told Radio.com that he wants action to be taken against Brown for promoting the use of marijuana, as well as flouting a recent ban on public smoking. He said:

"He promoted an illegality. You can see from the video and yet he was let go free."

Osei-Owusu continued: "The last two days, I have been with the police and an investigation has commenced. The police have moved swiftly and they are not leaving anything unturned."

Organisers of the concert reportedly denied any drug use occurred on stage, calling the incident a "stunt".