A Zimbabwean activist, Mr Sten Zvorwadza, has been arrested after calling 93-year-old President Robert Mugabe “a dead man walking”.
Lawyers said on Wednesday that the arrest was the latest case of authorities cracking down on dissent.
Zvorwadza, the leader of a street vendor’s union, was charged with insulting or undermining the president in a press interview where he was also quoted as saying that Mugabe was “old” and “day-dreaming”.
Mr Zvorwadza is a prominent anti-Mugabe campaigner who has led several demonstrations calling on the veteran leader to step down.
Zimbabwe’s worsening economy has seen many people resorting to informal street vending due to massive unemployment.
Mr Zvorwadza is yet to appear in court, the Zimbabwe Lawyers for Human Rights (ZLHR) group said.
Authorities have often arrested critics of President Mugabe, who has ruled since 1980.
In March, two journalists were arrested over a report that the president, who travels abroad for regular medical treatment, was “in bad shape”.
A pastor was also detained after prophesying that President Mugabe would die on October 17 this year.
Last week police arrested a journalist who reported that President Mugabe’s wife Grace had donated second-hand underwear to supporters.
Despite his advanced age and weakening health, President Mugabe’s ruling Zanu-PF party has endorsed him as its candidate for the 2018 General Election.