Ghana’s main opposition party reacted with anger after one of its most influential leaders was sentenced to 20 years in prison, with hard labor, for illegal mining offences.

The New Patriotic Party (NPP) alleged that the historic sentencing against Bernard Antwi Boasiako, the party’s Ashanti Region Chairman, was politically motivated.

Boasiako, popularly known as “President Wontumi”, is the first high-ranking politician in Ghana to be convicted of illegal mining since the government began cracking down on the practice in 2017.

As well as receiving a jail sentence, Boasiako, who had denied the charges, was ordered to pay more than $10,000 (£7,450) in fines.

He appeared visibly shocked when the judge handed down the sentence in a court in the capital, Accra, on Monday.

The PNP politician was found guilty of “allocating mining rights without approval” and “facilitating an unlicensed mining operation” through his company, Akonta Mining.

Ghana is Africa’s top gold producer, but much of the country’s waters and environment have been polluted by illegal mining, known locally as “galamsey.”

Over the years, governments have attempted to address the problem, including by deploying the military, with little success.