People suffering from albinism have long been persecuted in East Africa and Tanzania in particular.It is estimated that more than 150,000 albinos live there, and at least 70 of them have been murdered in the past six years, often for superstitious reasons.Al Jazeera's Peter Greste travelled to Dar es Salaam, the capital of Tanzania, for the first part of our "Global Beliefs Versus the Law" series, where an education campaign has begun.