As South Sudan prepares to become officially independent in July, Reporters Without Borders says it is appalled by recent developments affecting press freedom and appeals in particular to the new country’s president, Salva Kiir Mayardit, to release the Darfuri journalist Mohammed Arku without delay. Employed by Sudan Radio Service, Arku was arrested by South Sudan’s security services in Wau on 11 May for taking photos without government permission, although the area where he was arrested is not a militarised one.

British firms have acquired more land in Africa for controversial biofuel plantations than companies from any other country, a Guardian investigation has revealed. Half of the 3.2m hectares (ha) of biofuel land identified - in countries from Mozambique to Senegal - is linked to 11 British companies, more than any other country. Liquid fuels made from plants - such as bioethanol - are hailed by some as environmentally-friendly replacements for fossil fuels. Because they compete for land with crop plants, biofuels have also been linked to record food prices and rising hunger. There are also fears they can increase greenhouse gas emissions.