Police arrested a Zambian opposition leader, Saviour Chishimba on Thursday and said he would be charged with defaming President Edgar Lungu, an offence that carries a maximum five-year prison term.
Officers did not say how  Chishimba, the head of the United Progressive People (UPP) party, had defamed the president.
Chishimba hit the headlines in July criticizing Lunguâs decision to impose emergency powers and suggesting the president should go to hospital for mental tests.
Political tensions in Zambia, once seen as one of Africaâs more stable and functional democracies, have been rising since main opposition leader Hakainde Hichilema was arrested on treason charges in April.
Lungu said on July 6 that he had invoked emergency powers to deal with âacts of sabotageâ by his political opponents, after fire gutted the southern African countryâs biggest market.
The president said the measure would safeguard investments in Africaâs second-biggest copper producer which is in talks with the International Monetary Fund over a financial aid package.
Police said Chishimbaâs offence took place between July 1-8.
âHe has since been detained in police custody and will be charged once the officers are done with processes,â police spokeswoman Esther Mwaata-Katongo said.
