Egyptian Vice President Omar Suleiman said on Thursday that neither President Hosni Mubarak nor his son Gamal, who was widely seen as a possible successor, will run in the upcoming presidential elections in September, state media reported.

Earlier Thursday, Suleiman called on security authorities to release detained protesters "not involved in criminal acts," state news agency MENA said.

New Egyptian Prime Minister Ahmed Shafiq on Thursday apologized for deadly unrest between supporters and foes of President Hosni Mubarak on Cairo's Tahrir Square, state television reported.

"I offer all my apologies for what happened yesterday and there will be an inquiry," Shafiq told state television as the fighting on Tahrir Square raged for a second day with at least seven people dead.

Prime Minister Nuri al-Maliki told U.S. diplomats in 2009 that neighboring Iran and Syria were providing weapons to insurgent groups within Iraq, a leaked document showed Thursday.

Maliki's comments to then-U.S. ambassador to Baghdad Christopher Hill came in the midst of a year-long diplomatic row with Damascus that prompted both Iraq and Syria to withdraw their respective ambassadors, while U.S. officials have long alleged that Iran backs militia groups operating inside Iraq.

Gunmen firing on protesters in Cairo's Tahrir Square killed four people on Thursday as the thousands demanding President Hosni Mubarak go stood firm in their increasingly bloody 10-day revolt.

"All (four) were killed by gunshot, with one hit in the head," said Dr. Mohammed Ismail, at a makeshift clinic in Abdulmenem Riad Square, next to Tahrir (Liberation) Square, taking the death toll over the past 24 hours to seven.

Tens of thousands of protesters massed on Thursday at Sanaa university for a "day of rage" against Ali Abdullah Saleh's rule, while a similar number of loyalists flooded a central square in support of the embattled Yemeni president.

With Saleh supporters, some of them armed, taking over Al-Tahrir square from Wednesday night, protest organizers were forced to change the planned venue of their demonstration.

Anti-government protests that have shaken Egypt must end before talks with the opposition can start, Vice President Omar Suleiman said Wednesday, calling on protesters to respect a curfew and go home.

Suleiman, the veteran intelligence chief appointed to the office of vice president last week, urged demonstrators to respect an earlier call from the Egyptian army and return to their homes, state media said.

World powers said Wednesday that the transition towards democracy in Egypt must begin immediately and called for calm amid clashes in Cairo after Hosni Mubarak vowed to cling to office until September.

U.N. Secretary General Ban Ki-Moon called attacks on peaceful protestors "unacceptable" as pro- and anti-Mubarak demonstrators fought each other in the city's central Tahrir Square, leaving at least 500 injured.

Supporters of President Hosni Mubarak stormed a crowded anti-regime rally in central Cairo on Wednesday, sparking pandemonium in which at least 500 people were hurt and one killed, witnesses said.

Partisans from both sides threw stones and set on each other with sticks and fists in battles that raged for hours in Tahrir Square, the epicenter of anti-regime demonstrations, a day after Mubarak vowed to see out the rest of his term.

The Egyptian military called Wednesday for an end to more than a week of demonstrations against President Hosni Mubarak, throwing its support behind his embattled regime hours after he defiantly rejected demands to step down immediately and said he would serve out his term in office.

The declaration was a clear shift in the stand of the army, which gave a tacit endorsement to the movement on Monday by saying it would not use force against protesters, and that they had legitimate demands.

The United States is conducting a manhunt for a previously unknown group believed to be involved in the planning of the 9/11 attacks, according to a US cable published in Wednesday's Telegraph newspaper.

In the memo, leaked by the WikiLeaks website, a US official in Qatar told the Department for Homeland Security in Washington that three Qatari men were under suspicion of conducting surveillance operations on the attack sites.