Thousands of Egyptian anti-government protesters gathered in Cairo's Tahrir Square Sunday afternoon after a morning of relative quiet in the capital.Two soldiers standing guard next to a tank were working with several young men in civilian clothes to check the IDs and bags of hundreds protesters arriving to call for Egyptian President Hosni Mubarak to step down. RELATED:Netanyahu on Egypt unrest: The aim is to maintain stabilityLooting engulfs Cairo, other Egyptian citiesThousands of Egyptian protesters defy curfew in CairoEditorial: A region in fermentIsrael keeps diplomats in Egypt, but pulls out dependentsThey found a kitchen knife hidden in a plastic bag carried by a man in his 20s as he attempted to enter the square. The soldiers wrestled the man to the ground, beat him and put him inside their tank.Some 4,000 protesters chanted slogans against Mubarak in the square, the main gathering point for protesters since anti-government demonstrations began Tuesday, emboldened by Tunisians' success in driving out their president earlier in the month.Army helicopters were flying low over Cairo and entire neighborhoods remained without any troops two days after Mubarak called the army out on the streets. But many Cairo neighborhoods and other parts of the country remain untouched by looting or street crime.attacked at least four jails across Egypt before dawn Sunday, helping to free hundreds of Muslim terrorists and thousands of other inmates as police vanished from the streets of Cairo and other cities.The army sent hundreds more troops and armored vehicles onto the streets of Cairo and other cities but appeared to be taking little action against gangs of young men with guns and large sticks who were smashing cars and robbing people.Those who fled included 34 members of the outlawed Muslim Brotherhood, Egypt's largest and best organized opposition group. The Muslim Brotherhood's lawyer, Abdel-Monaem Abdel-Maqsoud, told The Associated Press the 34 were among scores rounded up by authorities ahead of the large anti-government demonstrations on Friday. The escapees included at least seven senior members of the group. At least one Nile-side shopping mall in Cairo was on fire after being looted the previous day.