Egypt after Mubarak: Slow pace of reform fuels anger
After weeks of mainly peaceful protests, Egypt's post-revolution crisis is entering a more violent phase of confrontations.
For two days running, demonstrators have marched from Tahrir Square to the headquarters of Egypt's military rulers, the Supreme Council of the Armed Forces, at the defence ministry.
There have also been angry confrontations in the second city of Alexandria and in the canal city of Suez.
Witnesses estimate that as many as 20,000 people joined the Cairo march on Saturday. By moving on the defence ministry they were challenging an unspoken "red line".
Even during the revolution in January and February there were only a few protests outside the defence ministry and the nearby presidential compound.
The protesters are angry over the slow pace of change, the continued use of military tribunals to try civilians and what they see as a reluctance to bring former regime officials to trial.
The increasingly aggressive response to their demonstrations just compounds their fury.
To protect the defence ministry the military blocked the road with vehicles and barbed wire.
But witnesses said the violence came initially from men in plain clothes who threw rocks and petrol bombs at the protesters and ran in from side streets armed with knives and clubs.
As the situation escalated, the army fired teargas into the crowd.
Gunfire was also heard, though it is believed to have been soldiers firing blanks in the air.
In a statement after the first march on the defence ministry on Friday, the ruling military council praised local people for forming a human shield to keep protesters away from the military headquarters.
But the opposition believe the military has revived the strategy of former President Hosni Mubarak's regime, sending out plain-clothes thugs to attack demonstrators, then denying responsibility.
The military council have always insisted they will not attack peaceful protests.
The army in Egypt enjoy a good deal of public support and trust, enhanced by their decision not to open fire during the revolution that unseated Mr Mubarak.
They also know that many Egyptians are weary of the continuing protests that block traffic in the centre of Cairo and other cities, and are blamed by some for harming the economy and preventing the country getting back to normal.
But the military are also, clearly, very nervous.
They hold substantial power, and are widely suspected of profiting from corruption under Mr Mubarak.
They must fear that the public mood could turn against them very quickly, particularly if soldiers did open fire on peaceful protesters.
Conflicting statements from the army in recent days illustrate their dilemma.
The ruling military council targeted one of the youth groups, the 6 April movement, and accused them of trying to drive a wedge between the people and the army.
But Field Marshal Mohamad Hussain Tantawi, in his first public address since taking control in February, pledged to work for a democratic Egypt and praised the role of Egyptian youth in the revolution earlier this year.
Another complication is the role of Islamists.
They are considering calling for a so-called "million-man" march on Friday to press for their vision of Egypt's future.
The mainly secular protesters in Tahrir Square may fear they could be overwhelmed by supporters of the Muslim Brotherhood, still the most organised mass movement in Egyptian politics, even though their precise level of support is disputed.
All of this comes as the date approaches for the trial of former Mr Mubarak on 3 August.
There continue to be conflicting reports about his health. Doctors have denied that he is in a coma, or that he has cancer.
The general impression, though, is that he is not well.
His lawyer is bound to argue for the trial to be postponed on grounds of ill-health.
Many in the opposition, and relatives of those killed during the revolution, will be deeply sceptical about any such claims.
If the trial is put off, there is the real danger of a major outburst of anger on the streets of Egypt.