Johannesburg's city streets 'go green' for festival

The Ecomobility World Festival has been taking place in Johannesburg in South Africa, with people being encouraged to get out of their cars and instead walk, cycle, and use public transport.

The aim is to reduce greenhouse gas emissions, and encourage cities around the world to change their transport policies.

The BBC's Christian Parkinson reports from Johannesburg, where the business district has ''gone green''.