Zimbabwean police say they have arrested 170 black market money dealers in a campaign against currency trading which they say has caused the prices of imported goods to rise.

It comes days after the central bank suspended four top directors alleged to be involved in black market trading.

A young communication strategist hired by the finance minister exposed the central bank's alleged involvement in the currency black market shortly after his appointment.

But within three days William Mutumanje, known as Acie Lumumba, was fired and his appropriateness for the role questioned.

Mr Mutumanje had claimed there was a rift between Zimbabwe's President Emmerson Mnangawa and his Vice-President Constantino Chiwenga.

He also threatened to expose a businessman allegedly financing the government who he said was behind major cartels.

The question remains whether this is the first real attempt to clean up black market trading, or whether Mr Mutumanje was being used to settle scores between former allies.