Scores of young men, coughing and gasping for air stumbled into dark side streets off Cairo's Tahrir Square to escape the acrid smoke during the to-and-fro battle with police.

But undeterred, tens of thousands still thronged the square peacefully late into the night on Wednesday to protest at the deaths of more than 30 people in the violence and reject the army's offer of a referendum on its rule.

In light of the violence, Interior Minister Mansour el-Essawy presented a report to the military council proposing a postponement of the parliamentary election planned for November 28.

The election, due to begin on November 21, has been billed as Egypt's first free vote in decades.

The army and the Muslim Brotherhood, which expects to do well in the election, says it must go ahead but many protesters are unwilling to trust the army to oversee a clean vote and hand real control of the country to the winner.

The generals' popularity has waned in the nine months since they nudged President Hosni Mubarak from office and swore to steer the country toward civilian democracy, as suspicion grew that they were manoeuvring to stay in power beyond elections.