Washington: Deadly clashes between supporters and foes of Egyptian President Hosni Mubarak on Cairo's Tahrir Square are to be the subject of an inquiry, state television quoted Prime minister Ahmad Shafiq as saying yesterday.

The announcement came after US Secretary of State Hillary Clinton urged Egypt's newly named vice-president to hold accountable those responsible for violence in Cairo on Wednesday, the US State Department said.

Clinton spoke by telephone with Omar Sulaiman, Egypt's intelligence chief who was elevated to vice-president by Egyptian President Hosni Mubarak, to make the point, State Department spokesman P.J. Crowley told reporters.

"She emphasised, again, our condemnation of the violence that occurred Wednesday, encouraged the government to hold those responsible fully accountable for this violence," Crowley told reporters.

"We don't know, at this point, who did it." Wednesday's clashes left five dead and 800 injured with no ambulances in sight and a makeshift clinic trying desperately to tend to the wounded.

The running clashes took place for over 12 hours with daybreak witnessing an escalation in the deteriorating situation as gunfire was being heard in this city of 18 million.

Salma Al Tarzi, an anti-government protester, told Al Jazeera there were many wounded people. "There are no ambulances in sight, and all we are using is Dettol," she said.

"We are all so scared."

Aisha Hussain, a nurse, said dozens of people were being treated at the makeshift clinic.

"People are coming in with multiple wounds. All kinds of contusions.

"We had one guy who needed stitches in two places on his face.

"Some have broken bones," she was quoted as saying.

Mubarak supporters, throwing petrol bombs, wielding sticks and charging on horses and camels, assaulted anti-Mubarak demonstrators in Cairo on Wednesday after the army told the protesters to go home.

CNN crew attacked

CNN’s Anderson Cooper said he and his crew were punched and kicked in Cairo on Wednesday by supporters of Egyptian President Hosni Mubarak, but that they escaped with just scratches as anti-government protests turned deadly.

The incident occurred as supporters of Mubarak rushed a crowd of his detractors, charging on horses and camels and wielding sticks and petrol bombs. The anti-Mubarak protesters fought back by throwing rocks at their attackers.

Cooper told Reuters in a phone interview from Egypt that he and his CNN crew were walking through a crowd of Mubarak supporters heading toward the melee, when a man tried to grab their camera.

Members of the crowd punched and kicked Cooper in the head and body, and set upon the rest of the crew, including female producer Maryanne Fox, he said.