Six Zambians and five Egyptians have appeared in court after a mystery plane landed in Lusaka with more than 100kg of counterfeit gold, nearly $6m (£4.8m) and weapons on board.
A senior Zambian police officer is among those arrested.
He has been charged with espionage.
Court papers are also reported to list a former Egyptian military officer and businessman.
The Egyptian authorities have claimed that the aircraft is privately owned, and only transited through Cairo.
The suspects face up to 30 years in jail if convicted.