Nevsun Resources Ltd. is denying complicity in human rights violations at a copper-gold project in Eritrea; according to a lawsuit, filed by three former workers in British Columbia Supreme Court, laborers were “forced” to construct the Bisha site in east Africa under threat of torture.

Vancouver-based company officials are “confident the allegations are unfounded,” said CEO Cliff Davis. “Based on company-led and third-party audits, the mine has adhered to international standards of governance, workplace conditions, and health and safety;” the mine lies 90 miles west of the capital city of Asmara.

Nevsun has a 60% stake in Bisha Mining Share Co. in a joint venture with state-owned Eritrean National Mining Corp. The asset produced only gold until 2013, when copper and zinc output ensued. Production of up to 90,000 copper tons along with zinc production is pending 2016.