Prediction time: How long until the Mubarak regime crumbles?

CAIRO (AP) – Egyptian army tanks and soldiers cleared away pro-government rioters and deployed between them and protesters seeking the fall of President Hosni Mubarak, moving to halt violence as the prime minister made an unprecedented apology Thursday for the assault by regime backers that turned central Cairo into a battle zone.

Prime Minister Ahmed Shafiq said the attack Wednesday on the anti-Mubarak protesters was a “blatant mistake,” acknowledged it was likely organized and promised to investigate who was behind it.

The protesters accuse the regime of organizing the assault, using paid thugs and policemen in civilian clothes, in an attempt to crush their movement. Government supporters charged the protest camp in central Tahrir Square Wednesday afternoon, sparking uncontrolled violence that lasted until the next morning, as the two sides battled with rocks, sticks, bottles and firebombs and soldiers largely stood by without intervening.

Thursday morning, the army fanned out to separate the two sides and allowed thousands more protesters to enter their camp in the square. Soldiers then stepped aside as the anti-government side surged ahead in the afternoon in resumed clashes.

With volleys of stones, the protesters pushed back their rivals swarmed onto a nearby highway overpass that their regime supporters had used as a high ground to batter them.

At the same time, Mubarak supporters carried out a string of attacks on journalists around the square. One Greek print journalist was stabbed in the leg with a screwdriver, and a photographer was punched, his equipment smashed. Arab TV network Al-Jazeera reported two correspondents attacked. The army started rounding up journalists, possibly for their own protection.

Shafiq’s highly unusual apology and the army intervention suggested at least some in the regime want to step back from Wednesday’s dangerous turn — the first outbreak of street violence between the two sides in what is now 10 days of unprecedented protests demanding Mubarak, unquestioned leader for nearly 30 years, quit power.