Mohamed ElBaradei: Egypt's next president?

Like the protesters who brought down the president of Tunisia this month, the predominantly young demonstrators who have brought Egypt to the brink of revolution have so far lacked an important asset: a figurehead.

Not even the Muslim Brotherhood, a banned Islamist movement that is Egypt's most credible opposition, has attempted to fill the vacuum. The movement joined the protesters three days late - and anyone worried about an Islamist takeover may take comfort in the words of Mohammed Mursi, a spokesman for the Muslim Brotherhood, who is quoted in the Guardian saying: "We are not pushing this movement, but we are moving with it. We don't wish to lead it but we want to be part of it."

So the stage is set for a heavyweight figure to take up the protesters' cause. And it looks like that person is going to be Mohamed ElBaradei. Westerners who have heard of 68-year-old ElBaradei will know him as the former head of the International Atomic Energy Agency, the body charged with monitoring nuclear proliferation. His work for the IAEA saw him and the agency jointly awarded the Nobel Peace Prize in 2005.

Since leaving the IAEA in 2008, ElBaradei, the son of a pro-democracy lawyer, has been busy organising opposition to Mubarak's 30-year reign as Egypt's president. Last year, he helped found the National Association for Change, a movement which united Egypt's rudderless opposition groups, including the Muslim Brotherhood, and hopes to bring about a peaceful transition to democracy.

Speaking in Vienna this week, ElBaradei made it clear he was returning to Egypt to lead. "If people, in particular young people, if they want me to lead the transition, I will not let them down. My priority... is to see a new regime and to see a new Egypt through peaceful transition.

"I advise the government to listen to the people and not to use violence. There's no going back."

ElBaradei was detained almost as soon as he arrived in Egypt, but not before he'd told the Guardian: "I'm sending a message to the Guardian and to the world that Egypt is being isolated by a regime on its last legs."

It is hard to see how the ailing 82-year-old president Hosni Mubarak, who is yet to appear in public since the protests began, can survive the current wave of public anger. In a pattern that will be familiar to Tunisians before the resignation of their own president earlier this month, Mubarak's son Gamal - once thought a likely successor - is reported to have fled Egypt.

Today's protests, dubbed "the Friday of rage", are in defiance of a supposed ban and are being attended by thousands, despite a new wave of arrests overnight and the deployment of elite riot police units.

There are rumours of a pro-government militia called Ikhwan al-Haq, who it is feared will mingle with protesters and give the police a pretext for upping the violence - although this might be part of a campaign of disinformation on the part of the government.

And in a desperate attempt to prevent protesters from communicating with each other via sites such as Twitter and Facebook, the authorities have shut down the entire internet. Mobile phone networks have also been cut off in parts of the country where unrest is occurring. ·