Zambian police have recorded statements from opposition presidential candidate Brian Mundubile and his running mate Makebi Zulu in connection with alleged treason.
Police spokesperson Godfrey Chilabi confirmed the two leaders of the National Reconciliation for Unity and Prosperity party were interviewed by law enforcement officers on Thursday and remain in custody as investigations continue.
The development follows recent arrests of activists accused of plotting an armed insurrection.
Earlier this month, police detained 11 people after a raid in Lusaka uncovered restricted military weapons and ammunition.
Authorities linked the suspects to illegal training camps and said the operation posed a serious threat to state security.
Government officials have described the arrests and ongoing inquiries as part of efforts to safeguard national stability.
Police say further information will be provided as investigations progress.
JN/APA