A fatal crackdown on illegal mining in Ghana has prompted a protest from Beijing, underlining the swelling backlash on Chinese investment across Africa.

The gold-rich nation has become a capital for illegal miners – both Chinese and Ghanians – and last week a raid, part of the latest crackdown on illegal mining which saw the arrest of more than 90 Chinese miners, left a 16-year old Chinese boy dead.

“Most of these Chinese illegal miners are heavily armed and shoot at anyone that gets near them. In this case, they opened fire when police tried to arrest them,” Richard Kofi Afenu, sectoral policy and planning manager at Ghana’s Mineral Commission, told Financial Times. “It is not as though police wanted to shoot them,” he said.

Beijing demanded Monday that Ghana initiate a full investigation and “uphold the safety and legal rights of Chinese citizens and businesses”.

“The Ghana government should start from the source of the issue, crack down severely on the middlemen, the traffickers and the illegal miners, and curb their illegal activities instead of just arresting victim Chinese citizens,” Chinese ambassador to Ghana Gong Jianzhong told an interview with state-run Chinese radio.

China has poured in billions of investment in Africa giving them a wider access to the continent’s resources which has stirred discontent in the countries involved.