Egypt's military said on Tuesday it strongly regretted attacks on female demonstrators as footage of soldiers beating women fuelled deadly anti-military protests in Cairo for a fifth straight day.

The ruling generals, facing a backlash after footage circulated of soldiers beating female protesters and partly stripping a veiled woman as they dragged her, pledged action against those responsible in an unusually contrite statement.

But it came hours after the country's forensics chief cast further doubt on their credibility when he said most those killed in the protests died of gunshot wounds, despite military denials that they fired on protesters.

"The Supreme Council of the Armed Forces expresses its strong regret to the great women of Egypt over transgressions that occurred during recent incidents in the protests outside parliament and the cabinet," it said in the statement.

The military respected the right of women to protest and had taken "all legal measures to hold accountable the people responsible for these violations," said the statement posted on its official Facebook page.

Thousands of women and men marched on Tuesday to Tahrir Square, epicentre of the democratic uprising that overthrew president Hosni Mubarak, to denounce the attacks as sporadic clashes with police continued nearby.

The health ministry said 14 people had been killed since Friday, state television reported, but it did not say whether any were killed on Tuesday.

The ministry had earlier denied reports by medics in the square that four people were killed overnight.

One witness told AFP that a 14-year-old child had been treated in the field hospital for a bullet wound to the chest.

Health ministry official Adel Adawi told state television that of more than 600 people injured since Friday, 106 remained in hospital.

"One man is currently undergoing surgery after a gunshot went into his back and out through the stomach," Adawi said.

Forensics chief Ehsan Kamil Georgi told the official MENA news agency that nine people killed "were wounded by gunshots."

Another of the dead "breathed his last breath in detention in the south Cairo court, before he was presented to the prosecution. The cause of death was traumatic injury to the head that causes internal bleeding," he said.

Pictures and footage of troops kicking the woman, as one soldier apparently grinned, sent shockwaves through the independent media. Soldiers were also taped beating another woman.

"The forces that violate the honour (of women)," read a headline in the independent daily Al-Tahrir above a picture of a soldier grabbing a woman by the hair as another raised a club over her.

US Secretary of State Hillary Clinton on Monday accused Egyptian authorities of failing women as she denounced the stripping and beating of the female protester as "shocking."

In unusually strong language, she accused Egypt's new leaders of mistreating women both on the street and in politics since the revolt brought down Mubarak.

"This systematic degradation of Egyptian women dishonours the revolution, disgraces the state and its uniform, and is not worthy of a great people," said Clinton.

On Monday, the SCAF, which took charge after Mubarak's February ouster, said the army "does not use force against protesters" but called those in Tahrir "people seeking to destroy the state... not the honourable people of the January 25 revolution."

However, it admitted troops had attacked the veiled female protester.

"Yes, this happened. But you have to look at the circumstances around (the incident)," said SCAF General Adel Emara. "We are investigating it, we have nothing to hide."

Meanwhile, human rights groups and dissidents slammed retired army general Abdelmoneim Kato -- an adviser to the military -- for saying some in Tahrir were "street kids who deserve to be thrown into Hitler's incinerators."

Presidential hopeful and former UN nuclear watchdog chief Mohamed ElBaradei said such statements showed "a deranged and criminal state of mind."

The Arabic Network for Human Rights Information said Kato's comments "incite hatred and justify violence against citizens."

A group of newly elected members of parliament -- including Islamists and liberals -- on Monday announced a daily protest outside the Cairo Supreme Court, demanding an immediate end to the violence against protesters and an investigation.

UN leader Ban Ki-moon accused Egyptian security forces of using "excessive" violence against protesters while Clinton urged "Egyptian security forces to respect and protect the universal rights of all Egyptians."

British Foreign Secretary William Hague called the violence "inconsistent with the democratic process in which Egypt is now engaged."

And rights watchdog Amnesty International urged arms suppliers to halt transfers to Egyptian forces.