Journalists in Tunisia have gone on strike to protest against press restrictions imposed by the Islamist-led government.

Tuesday's strike, called by the National Union of Tunisian journalists, comes a day after a journalist whose arrest caused an outcry, was freed on bail.

"It's a victory for everyone who supports freedom of expression over those who, with the help of the judiciary, would like to suspend this freedom and settle their scores with people not willing to give it up," Zied el-Heni told AFP news agency after bail was paid for his release.

Heni was placed in pre-trial detention on Friday for accusing the public prosecutor of fabricating evidence implicating cameraman Mourad Meherzi in an egg-throwing attack on a minister.

The cameraman spent three weeks in prison before his release on bail on Monday, while the egg-thrower - a film-maker - remains in custody.

On Friday evening, after Heni was detained, a judge agreed to grant him bail, but it was not possible to pay the bail money until Monday morning, so the reporter spent the weekend in jail.

"The file must now go back to the judge who must listen to our arguments. In my opinion this case should be dismissed," said Heni's lawyer Abdelaziz Essid.

His comments were echoed by Reporters Without Borders, which called his pre-trial detention "totally unjustified" and designed to silence any criticism.

'Sacred principles'

Ennahda, the Islamist party that heads Tunisia's ruling coalition, said the accusations were wrong and formed part of a slander campaign against it.

The journalist's detention has been preceded by other cases that have stoked fears in Tunisia that Ennahda, the judiciary and the police are trying to stifle freedom of expression, seen as a key achievement of the 2011 revolution that triggered the so-called Arab Spring.

Two rappers were convicted at the end of August and sentenced to 21-month jail terms over songs deemed to be defamatory towards the police force.

The singers - who are on the run - had not been told there were charges against them, let alone that there was a trial.

However, the Tunisian presidency on Monday reaffirmed its commitment to "the sacred principles of freedom of expression and opinion".

Media rights in Tunisia are theoretically governed by two decrees adopted after the revolution, designed to guarantee press freedom and regulate audio-visual media.

But the public prosecution continues to rely extensively on the penal code inherited from the ousted regime of Zine El Abidine Ben Ali, under which press offences can be punished by jail terms.

Source: Al Jazeera and agencies