Presidential election campaign under way in Zanzibar

Campaigning is under way in Tanzania’s semi-autonomous state of Zanzibar for what is expected to be a fiercely contested presidential election next month.
The result could trigger another potentially violent fallout between the governing party and the opposition following the disputed election five years ago.
One of the main issues is the status of Zanzibar’s union with mainland Tanzania.
Al Jazeera’s Catherine Soi reports from neighbouring Kenya.