South Sudan authorities have banned the chief editor of an Arabic newspaper, Al Watan, from leaving the country for allegedly publishing content critical of the government.
Michael Christopher was on Monday afternoon seized aboard Kenya Airways flight for Nairobi at Juba International Airport.
Mr Christopher said he was forcefully disembarked from the plane by officers from the spy agency, National Security Service (NSS), acting on orders of the "highest authority".
"When I came down, I asked them what's happening. They told me that they had an order from the highest authority to confiscate my passport and prevent me from travelling," Mr Cristopher told journalists in Juba.
He said that his passport was yet to be returned to him.
In March, the country's media regulator suspended Al Watan accusing it of non-compliance and operating without a licence.
South Sudan Media Authority (SSMA) said the Al Watan, published daily, failed to meet terms of its licence.
"This is to inform the public and media houses that the media authority has suspended the operation of Al Watan Arabic newspaper with effect from March 27, 2019, for gross non-compliance with the licence terms and conditions in accordance with section 45 (1) of the media authority Act, 2013, read together with Rule 4 of the media authority regulations on print media, 2018," the regulator said at the time.
Earlier, Mr Christopher had been forced to apologise for covering anti-Bashir protests in neighbouring Sudan.
South Sudan reporters are often the target of government officials, especially when highlighting human rights violations and abuse of power.
At least 10 journalists have died in the line of duty since the country seceded from Sudan in 2011.
Several media outlets have also been shut down by the government for critical coverage of the country's affairs.
The country ranks 139 out of 180 on the World Press Freedom Index by advocacy group Reporters Without Borders.