Tensions are high in Egypt after a deadly weekend in which the Army, for the first time since it rolled into the streets Jan. 28, appeared to have used live ammunition to disperse protesters from Cairo's Tahrir Square, killing at least one and injuring scores.

The Supreme Council of the Armed Forces, which has ruled the country since pro-democracy protesters forced the ouster of former President Hosni Mubarak on Feb. 11, said Saturday that it did not fire live ammunition at protesters. It blamed the violence on thugs paid by remnants of Mr. Mubarak’s regime to turn popular opinion against them.

But multiple witnesses of Friday's clashes described seeing and hearing gunfire from the Army, and many of the protesters now say they've been betrayed by the same institution that had acted as the guardian of their revolution.

More than 1,000 protesters continued to occupy the square Sunday, barricading the entrances with burned-out trucks and barbed wire, as the now-famous epicenter of the revolution began to look more like the battlefield it resembled in February. And in the aftermath of the confrontation, many seem unsure of what comes next.

“This is a very critical situation now. I don’t know what we’ll do,” says Ahmed Salah, who was present before dawn Saturday when the military attacked the protesters. “But now people know that the Army is not protecting the revolution. So there’s no need to play games anymore, to pretend.”

Adding to the sense of uncertainty Sunday, Saudi Arabian television channel Al Arabiya broadcast an audio recording of Mubarak – now under house arrest in the Sinai resort town of Sharm el-Sheikh – denying having used his position to amass wealth and threatening to sue those who damaged his reputation.

The few thousand who decided to occupy the square overnight Friday were remnants of the tens of thousands who came earlier in the day to criticize the military council temporarily in charge of the nation and demand that Mubarak, his family, and his cronies be tried for corruption. As many as two dozen Army officers in uniform joined them, against orders, to protest corruption in the high ranks of the Army and call for a civilian presidential council, rather than the military officers, to rule Egypt until new elections are held.

Dissidence within the ranks was apparently a red line for the Army.

In the early hours of Saturday, during which a curfew is still in place, Army and riot police descended on the square, where the dissident officers were camped out with protesters. Witnesses say they used tear gas, but also described massive amounts of gunfire as the military cleared the square. Some of the dissident officers were captured, while witnesses said others escaped wearing civilian clothes given to them by fellow protesters. Egypt’s health ministry says one person died, although witnesses say the number was higher.

By daytime Saturday, the protesters had regrouped in Tahrir Square. The skeletons of several personnel carriers lay smoking, some used as barricades, and youths grabbed the barbed wire left behind by the military to block off all the streets entering the square. People gathered around a large dried pool of blood where witnesses say a protester was shot. But the game plan for going forward was unclear.

The military council offered a concession Saturday, announcing it would replace some Mubarak-era governors. And shortly after the audio recording of Mubarak was aired Sunday, Egypt’s public prosecutor announced he had summoned Mubarak for an investigation, not just into embezzled funds, but also into the killing of protesters. Mubarak’s sons Alaa and Gamal will also be investigated.

In the recording, Mubarak, who sounded weary, said he would allow investigation into his funds and holdings to prove he did not have bank accounts or property outside Egypt. He also said he was “hurt” by “unjust campaigns and false allegations” to smear his reputation.