AFP, Berlin, 14 June 2009 - Several foreign news organisations complained Sunday that Iranian authorities were blocking their reporters from covering protests against President Mahmoud Ahmadinejad’s re-election. German public television channels ZDF and ARD said their reporters were not allowed to broadcast their reports, while the BBC said the signals of its Persian services were being jammed from Iran. The Dubai-based Arab news channel Al-Arabiya in Tehran was forbidden from working for a week and Dutch broadcaster Nederland 2 said its journalist and cameraman were arrested and ordered to leave the country. Foreign media converged in Iran to cover Friday’s presidential election, whose official result sparked violent protests in Tehran after Ahmadinejad was declared the winner by a landslide. Violence erupted for a second day on Sunday as supporters of Ahmadinejad’s closest challenger Mir Hossein Mousavi clashed with riot police. Mousavi denounced the election as a fraud and called for the vote to be annulled. The editors in chief of German public television channels ZDF and ARD sent a letter to the Iranian ambassador in Berlin accusing Iranian authorities of barring their reporters from doing their work. ARD correspondent Peter Mezger can no longer leave his hotel while ZDF journalist Halim Hosny and his colleagues have not been allowed to report on the events, their chief editors wrote. "We see a breach of freedom of the press and democratic principles," their editors said in their letter. Iranian authorities had already barred the journalists from filming and broadcasting their images in recent days, the editors said. ARD and ZDF insisted that they would "continue to report on the events in Iran" in a "critical, fair and independent" manner. The British Broadcasting Corporation said the satellites it uses for its Persian television and radio services had been affected since Friday by "heavy electronic jamming" which had become "progressively worse." Satellite technicians had traced the interference to Iran, the BBC said. "Any attempt to block BBC Persian television is wrong and against international treaties on satellite communication. Whoever is attempting the blocking should stop it now," said BBC World Service director Peter Horrocks. "It seems to be part of a pattern of behaviour by the Iranian authorities to limit the reporting of the aftermath of the disputed election," he said, noting that BBC world affairs editor John Simpson and his cameraman were briefly arrested after filming a report. Dutch public broadcaster Nederland 2 said NOVA journalist Jan Eikelboom and cameraman Dennis Hilgers, who had been in Iran for several days covering the election, "were filming in front of the headquarters of Mousavi, Ahmadinejad’s main rival, when they were arrested by police," the channel said in a statement. "They were pushed against a wall and their tapes were seized. Their filming permits were withdrawn and they have to leave the country immediately," it said. The Arab news channel Al-Arabiya said that its correspondent, who has been in Tehran for the past four months, had been "informed verbally" of the decision to shut down his office for a week. "We are not allowed to do any coverage. No reason was given, and there was no earlier warning," executive editor Nabil al-Khateeb told AFP. "I believe it is due to the current state of unrest." Belgian radio stations RTBF and VRT said their reporters were briefly detained and ordered not take pictures, Belga news agency reported. The correspondent of Spanish public channel TVE said during a live broadcast Saturday that police had confiscated a video of one the protests.