Unrest continues near Cairo's Tahrir Square
Unrest is continuing in Cairo as protesters step up their demand for Egypt's military rulers to resign.
Street battles with riot police have been heaviest around the fortified interior ministry located on a side street off Tahrir Square.
Gunfire was reported late on Wednesday but the interior minister said security forces were only firing tear gas.
The protesters have rejected a pledge by the ruling military council to speed up transition to a civilian government.
The BBC's Jeremy Bowen in Cairo says the violence threatens to overshadow next week's parliamentary elections.
He says public opinion on the protests is divided. Some Egyptians want elections to go ahead unhindered while others believe the military must be swept from power first.
The clashes, now entering their sixth day, are the longest outbreak of violence since the 18-day uprising that toppled former President Hosni Mubarak in February.
Since then a military council has been tasked with guiding the country's transition to democracy. The latest protests have been triggered by suspicions that the military intends to hang on to power.
On Tuesday Field Marshal Mohamed Hussein Tantawi, head of the Supreme Council of the Armed Forces, sought to defuse the situation by promising presidential elections by the end of June, six months sooner than planned. The military-appointed civilian cabinet also tendered its resignation.
"They [the military] were with Mubarak from the start," said Fatihia Abdul Ezz, 60, who had come to the square to protest.
"I came when I saw our sons being killed."
Groups of stone-throwing demonstrators have been locked in pitched battles in the streets between Tahrir Square and the interior ministry for several days.
Riot police blocking streets leading to the ministry have driven back the protesters with volleys of tear gas and rubber-covered steel buckshot.
Protesters have spoken of gunshots and injuries or deaths from live bullets but Interior Minister Mansour el-Essawy said security forces were only firing tear gas.
On state TV he said unidentified people were shooting from rooftops near Tahrir Square, Reuters news agency said.
At one point on Wednesday a truce was apparently brokered by religious leaders, but soon broke down and the clashes continued into the night.
There were also clashes in Egypt's second city, Alexandria, and in Ismailia, on the Suez Canal.
Television pictures from Ismailia showed armoured vehicles patrolling streets as security forces tried to disperse protesters with volleys of tear gas.
In Alexandria protests have been smaller than in Cairo, but one protester said clashes were continuing early on Thursday outside the security headquarters.
One protester, Mahinour, told the BBC the number of injured people there was increasing.
"Most of them are suffocating because of gas. This time they are not using tear gas, it's more nerve gas than tear gas. And as well there are some people injured by rubber bullets," she said.
Despite the clashes, the BBC's Wyre Davies in Alexandria says the appetite for conflict is lessening and people want their country to move on.
The main opposition group, the Muslim Brotherhood, is not supporting the protests and expects to do well in the parliamentary elections which start next week and will be staggered over several months.
Earlier on Wednesday, UN human rights chief Navi Pillay condemned the "clearly excessive use of force" by Egypt's security forces during the clashes.
She called for an independent inquiry into deaths since the weekend.
The health ministry said on Wednesday that 35 people had died in clashes since Saturday - all but four in Cairo. Hundreds more have been injured.
State news agency Mena reported that one person had been shot dead in the north-western city of Mersa Matruh as demonstrators tried to storm a police station.