TUNIS - Tunisian journalists and media figures on Thursday accused the government of clamping down on freedom of expression, as the Islamist-led state is criticised for tightening its grip on the press.

Two state-run newspapers said their new director, who they consider too close to the ruling Ennahda party, censored an article they were to publish criticising his appointment by the government.

And the head of a TV channel gave himself up to the authorities on Thursday under an arrest warrant, claiming this was ordered in retaliation for a political satire show his station aired.

International NGOs have recently criticised the Tunis government for seeking to manipulate the media, including by appointing new directors to head public media groups without consulting their staff.

"This is harassment," a journalist and unionist said of the alleged censorship by state-owned Dar Assabah press group director Lotfi Touati of newspapers Le Temps and Essabah.

The two dailies were to run an article criticising Touati's recent appointment to his position by the government, but he stopped it being printed overnight Wednesday and called the police to the office, Sana Farhat said.

"The new heads want to control the newspapers' editorial line," Farhat added, accusing the director of taking orders from the government.

She said the article, which was also to announce a September 11 strike, was replaced by commercials.

Meanwhile Sami Fehri, head of Ettounsiya TV, turned himself in to the attorney general's office almost a week after his arrest warrant was issued, his lawyer said.

In a video statement released during the night, Fehri said he was going to the attorney general to allege unlawful prosecution and an attack on freedom of expression.

"Freedom of expression with which we live since January 14 (2011, the day Ben Ali fled Tunisia) is threatened," said Fehri.

He believes his arrest was ordered because of his channel's satirical puppet show, which was recently and abruptly halted allegedly under pressure from the authorities.

Fehri last week told Express FM radio he would not fight the warrant.

"A huge machine has crushed us to death," he said of the government. "I would never have imagined it could happen like that. They have crossed every red line."

Official news agency TAP has said Fehri was being charged with "illegal use of Tunisian state television resources" during the rule of Ben Ali.

The authorities say they want to "clean up" the system of accomplices of the fallen regime, like Fehri who was an associate of Belhassen Trabelsi, brother of Ben Ali. Trabelsi has fled to Canada.

The warrant against Fehri came days after protests by Tunisian journalists accusing the government of seeking to curtail press freedom and take control of the country's media.

Reporters Without Borders on Wednesday condemned the government for tightening its control of state media, highlighting the "urgent need" for independent regulation of the broadcasting sector.