The Sudanese authorities have closed the Khartoum office of Arabic satellite television station al-Jazeera and detained one of its correspondents.
The country's official news agency accused al-Jazeera and its reporter Islam Salih Bello of lies and distortion.
Police raided the office on Wednesday, seizing equipment including cameras.
Staff said they had often received threats from Sudan's national security forces over their coverage of events.
An official statement from the Sudanese National Security Authority said al-Jazeera, through its Khartoum office and its correspondent, Mr Belo, "took to preparing and transmitting a number of programmes and materials stuffed with false information".
It accused the reporter of "poor, biased analyses and with pictures and scenes selected to serve [his reports'] ends."
The authorities' discontent stems from reports carried by the station regarding tuberculosis, landmine victims in Sudan and events in the western Darfur region.
The statement further accused the al-Jazeera correspondent of exploiting events "of provocation, lying, fabrication, distortion and colouring the facts in an unmistakably poor professional performance".
Mr Bello had also filed reports outlining how the Sudanese authorities had previously entered his offices and confiscated his broadcasting equipment.
In a report about the seizure, Mr Bello had said the authorities were security forces sent by the government.
But the authorities maintain that the men were customs officials "acting in a legal and civil manner".
They took transmission devices from Mr Bello that they deemed to have been imported illegally, the statement said.
Sudanese officials have said Mr Bello will remain under arrest and the al-Jazeera offices in Khartoum will remain closed until the station corrects the alleged factual errors.