Another Namib Desert Diamonds (Namdia) employee was arrested in connection with the N$315-million diamond heist at the company's premises last year.
The latest arrest brings the total of Namdia employees arrested in the case to four.
The heist on 18 January 2025 resulted in the death of Namdia protection officer Francis Eiseb.
Company spokesperson Beverley Coussement says: "This development follows continued collaboration between Namdia and law enforcement authorities as part of efforts to ensure full accountability and transparency."
The implicated staff member has been suspended immediately without pay, pending the outcome of an internal disciplinary hearing and a criminal investigation.
Coussement says Namdia commends the police for their efforts.
"We reiterate our full support to the Namibian Police and all relevant authorities involved in this investigation.
"Namdia will continue to cooperate fully to ensure all individuals involved are brought to justice," she says.