Egypt has shut down the Cairo operations of Al Jazeera as part of a crackdown against widespread anti-government demonstrations.
The move comes at a time when Al Jazeera is arguably at its most influential in its 15-year history, galvanising popular support against the regimes in Egypt and Tunisia and prompting the ire of rattled regional leaders.
The pan-Arab channel, which is owned by the Emir of Qatar, was quick to denounce Egypt's move as "silencing the voices of the Egyptian people".
Egypt has good reason to be worried. Al Jazeera was instrumental in disseminating the first grainy images of unrest and police brutality in Tunisia. Within weeks, protesters had ousted President Zine el-Abidine Ben Ali after 23 years in power. The images from Tunisia inspired others in the region similarly affected by grinding poverty and unemployment, and protests swept across the region to Libya, Yemen, Jordan and Egypt.
Al Jazeera may be a controversial force in the Middle East – often criticised for slanted reporting and pursuing an openly populist agenda – but is the first Arab channel to reach into homes across the region, outplaying tightly controlled state media. Nevertheless, it was slow to report on the protests in Egypt, leading instead with its exposure of 1,600 secret papers from Israeli-Palestinian peace negotiations. Analysts said it seemed probable that Qatar did not want to be seen instigating an uprising, but to many Egyptians, it smacked of betrayal. Instead, it was Facebook and Twitter that proved key in galvanising the protesters. But when Al Jazeera did finally join the fray after the protests turned violent, it provided some of the most comprehensive coverage of the clashes from Cairo, Alexandria and Suez, putting the state broadcaster to shame.
But it went a step too far when it aired an interview with Yusuf al-Qaradawi, a cleric and mentor of the banned opposition movement the Muslim Brotherhood, who called on President Mubarak to leave the country. The channel was promptly ordered off air.
But while the protests may well be seen as Al Jazeera's defining moment, the station attracts criticism in equal measure. The Palestinian Authority has accused the channel – widely seen as more sympathetic towards the rival Islamist movement Hamas – of a smear campaign aimed at provoking the Palestinians into revolt against their leaders. Protesters vandalised Al Jazeera's offices in Ramallah last week, accusing it of working for Israel.
The station also came under attack in Lebanon during riots last week. Supporters of the ousted Sunni premier accused the channel of supporting Shia militia Hezbollah, which they say is trying to put Lebanon under Syrian and Iranian control.