Dozens of Tunisian journalists and rights activists demonstrated in the streets of the capital, Tunis, to denounce "state repression" and attempts to intimidate the media.
The protest, organised by a journalists' union, SNJT, came three days after police arrested Noureddine Boutar, the director of a popular private radio station, Mosaïque FM.
Boutar is one of 10 public figures arrested since Saturday, mainly critics of President Kais Saied, including members of the Islamist-inspired Ennahdha party.
"The authorities, at all levels including the president and the prime minister, are seeking to repress press freedom and there are many indicators that prove this, such as military trials, decree-law no. 54, allegations over editorial outlines and other practises", denounced Amira Mohamed, vice-president of the SNJT journalists' union.
Dalila Ben Mbarek Msaddek, lawyer of detained radio director Noureddine Boutar, added "since they cannot arrest journalists, because it will clearly be perceived as a blow against freedom of expression, so they decided to arrest the head of the best and the most listened to media outlet in Tunisia.
By doing so, they are trying to silence all journalists and editors at the radio station who are very critical of the government, as well as other outlets".
Reacting to Thursday's protest, President Kais Saied rejected the allegations.
"Today, we hear about freedom of expression. Has a newspaper been banned once? Has a programme been banned? Has a single journalist been prosecuted for his or her journalistic work? Unfortunately, it's all lies", said the Tunisian President.
The demonstration came a day after Tunisia's main opposition coalition said the arrests were "violent and legally baseless".
On Wednesday the White House said it was "deeply concerned" by the spate of arrests.