The Iranian authorities have banned a daily newspaper and a weekly magazine as a crackdown on reformist media escalated in the Islamic republic.

Iran’s press watchdog revoked the licences of Etemad and Irandokht on the same day that security forces arrested the 49-year-old film-maker Jafar Panahi, who is a vocal supporter of the opposition leader Mir Hossein Mousavi.

The newspaper Etemad was banned for the first time in its eight-year history after publishing remarks made by the former Iranian president Mohammad Khatami, which suggested that the country is facing a “crisis”, the Iranian Labor News Agency reported.

Mohammed Ali Ramin, Iran’s deputy culture minister for media affairs, suggested that the ban was a “bitter decision” for the government to take.

“After repeated warnings and the persistence of the paper in breaching the regulations, the watchdog had no choice but to ban it,” Ramin said.

Specifically, the board said that the newspaper had violated press law number six, forbidding media organisations from revealing secret orders or publishing discussions of parliament’s closed sessions and trials.

The Press Supervisory Board also prohibited the publication of Irandokht; a magazine run by the family of the opposition leader Mehdi Karrubi that started out as a women’s weekly, but has since altered its focus to cultural and political issues.

No official reason has been given for this decision, but the Iranian journalist Masih Alinejad told CNN that the magazine was closed after Karrubi’s wife Fatameh sent a letter to the Supreme Leader Ayatollah Ali Khameini accusing him of abusing her son Ali.

The reporter for Etemad-e Melli said: “Now we are journalists without newspapers, and we really need help for what is happening in Iran to be heard.”

The press supervision body has been busy since the disputed re-election of president Ahmadinejad in June, with the leading business daily Sarmayeh banned in November and the popular publication Etemad-e Melli closed in August.

Highlighting the perilous situation facing many Iranian reporters, Ghanbar Naderi, a journalist for the Iran Daily, told Al Jazeera that continuing closures in the media have created a culture of self-censorship.

He said: “In these sensitive times, with the country under constant political pressure, as a journalist your first mistake will be your last.”

In a further move reflecting the continuing crackdown on dissenters, Jafar Panahi, one of Iranian cinema’s most prominent directors, is
being held at an undisclosed location after he was arrested with his wife, daughter and 15 guests at his home on Monday evening.

These arrests come just days after Iranian authorities released six journalists from Tehran’s Evin prison, including Mashallah Shamsolvaezin, spokesman for the Iranian Committee for the Defence of Freedom of the Press.

The New York-based Committee to Protect Journalists disclosed last month that Iran is now “far and away the world’s leading jailer of journalists”. This news follows the launch of a new campaign by a number of leading press freedom and free expression groups, including Index on Censorship entitled Our Society Will be a Free Society, which aims to release the journalists and writers imprisoned by Iranian authorities.