Espace TV and Kalac TV posted an image of two hands pushing apart steel bars against a backdrop of the national colors of red, yellow and green, with "A Day Without Press" written underneath.
Other news outlets shared visual variations on the same theme, while radio stations played a selection of somber music.
The protest was announced Monday after the ruling military shut down two radio stations owned by the Afric Vision group, limited access to popular websites and social media, and threatened to close any media that "undermines national unity."
Telecommunications Minister Ousmane Gaoual Diallo has denied any crackdown against Afric Vision or blocking of the internet.
The chronically unstable state has been run by the military since 2021, when President Alpha Conde, the country's first freely elected leader, was overthrown.
The junta has promised, in the face of international pressure, to restore civilian rule by the end of 2024, purportedly to give it enough time to carry out institutional reforms.
But it has arrested a number of opposition leaders and launched prosecutions against others after last year banning all demonstrations.
The opposition has called for fresh demonstrations in the capital Conakry on Wednesday and Thursday.
Guinea Media Stages News 'Blackout'
CONAKRY - Private media and online outlets in the West African state of Guinea on Tuesday launched a one-day boycott of news in protest at press and internet restrictions by the ruling junta.
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