A journalist with the privately-owned NewsDay newspaper, Obey Manayiti, is in police custody after he was arrested in Mutare on Monday.
Press reports indicate that Obey had gone to Mutare Central Police Station to report death threats made against him by Tawanda Mukodza, the ousted ZANU PF provincial youth chairman.
Manayiti told NewsDay that Mukodza spotted him in the city centre and pursued him, threatening him with death. The reporter is said to have jumped into a taxi and fled to the police station, where he intended to make a report.
However on arrival, Manayiti was arrested and charged with criminal insult after Mukodza had lodged an earlier complaint claiming the reporter had insulted him.
Manayiti was then asked to report back at the police station Tuesday, when he was charged under the Criminal Law (Codification and Reform) Act. He will spend the night in police cells and is expected to appear in court Wednesday. He is represented by Takaidza and Mubata Legal Practitioners.
A source at NewsDay said: "This case demonstrates the selective and partisan application of the law by the police. Instead of investigating both cases, they were biased in favour of a ZANU PF official."
Mukodza was the ZANU PF provincial youth chairman for Manicaland, before he was sacked on allegations of corruption, nepotism, provoking divisions within the ruling party and insubordination.
Nyasha Nyakunu, spokesman for media rights watchdog MISA-Zimbabwe, expressed concern at yet another arrest of a journalist but could not comment further as details of the case were still sketchy.
Zimbabwe's media environment remains one of the most tightly restricted in the world, characterised by arrests and harassment of journalists working for the independent media.
Last year, the US-based Freedom House ranked the country 172 out of 197 countries, the worst overall ranking in the southern Africa region.