Journalists and human rights activists had been targeted repeatedly by Egyptian authorities, with at least two dozen being detained or arrested, though some have since been released. Authorities seemed to be targeting television crews.

"This is a dark day for Egypt and a dark day for journalism," Committee to Protect Journalists Executive Director Joel Simon said in New York.

"The systematic and sustained attacks documented by CPJ leave no doubt that a government-orchestrated effort to target the media and suppress the news is well under way. With this turn of events, Egypt is seeking to create an information vacuum that puts it in the company of the world's worst oppressors, countries such as Burma, Iran and Cuba."  The US government joined other governments and non-governmental organizations complaining of attacks against media covering the clashes on Cairo's streets between supporters of Egyptian President Hosny Mubarak and opponents of the regime.

Secretary of State Hillary Rodham Clinton condemned "in the strongest terms" attacks on foreign reporters in the country. She said the assault on journalistic freedom is a violation of international norms and "unacceptable under any circumstances."  US State Department spokesman PJ Crowley said: "There is a concerted campaign to intimidate international journalists in Cairo and interfere with their reporting. We condemn such actions."  The New York Times reported that two its reporters were released Thursday after being detained overnight.

The British Broadcasting Corporation said Thursday that it was being targeted, and its equipment was being seized, in an attempt to stop its journalists from broadcasting out of Egypt.  "Egyptian security forces have mounted a systematic crackdown on journalists and human rights activists all over the city," said Peter Bouckaert with Human Rights Watch in Cairo.

One of his staff was arrested, as was a worker for Amnesty International.

Meanwhile, four Israeli journalists detained and released Wednesday returned to Israel by plane, the radio said. Images of the three were earlier broadcast prominently on Egyptian state television, with police officers holding up their passports to the cameras.  Several other foreign journalists, including from a French television station, and reporters of Qatar's al-Jazeera satellite channel were also reported arrested.

In Paris, Reporters Without Borders said it was "horrified by what appears to be an all-out witch hunt against news media that are covering events in Egypt."  The group said it was very concerned for all journalists currently in Cairo, especially before a major demonstration planned by Mubarak's opponents for Friday.

Secretary-General Jean-Francois Julliard said the regime had unleashed "its supporters in an unprecedented campaign of hatred and violence" against the media, with several news bureaux having been attacked.  "This has gone beyond censorship. This is now about ridding Cairo of all journalists working for foreign news media," Julliard charged, saying that "the highest level of the Egyptian government" must be held responsible for the attacks.  Reporters Without Borders was urging all news media to boost their coordination to gain as much security as possible for correspondents.  "We urge foreign governments and their embassies to provide the utmost diplomatic support for journalists from their countries when they find themselves in difficulty," Julliard said.  Amid various reports about attacks against media representatives, Swedish public broadcaster SVT said that one of its reporters had gone missing in Cairo while covering the protests. He was later reported hospitalized with stab wounds, "seriously injured but in stable condition," SVT said.  An unknown male voice had earlier answered the reporter's mobile phone and said in Arabic that Sundstrom had been detained and was "with the army," SVT's Olov Carlsson said.