Egyptians take part in a protest in Cairo, capital of Egypt, Jan. 30, 2011. Anti-government protests persisted for the sixth day across Egypt on Sunday as demonstrators demanded the ouster of President Hosni Mubarak. The curfew ordered by the Egyptian government, previously from 4 p.m. to 8 a.m., now runs from 3 p.m. (1300 GMT) to 8 a.m. [Cai Yang/Xinhua]

As hundreds of judges have reportedly joined the mass anti-government protests in Cairo Sunday, the large-scale riots in Egypt's major cities, which have continued into its sixth day, started to arouse more international responses.

Thousands of people were still seen shouting slogans and waving national flag as they flooded the Tahrir Square in downtown Cairo, which was guarded by armored vehicles, tanks and full-armed soldiers.

Witnesses said the military presence grew stronger than in the previous days, and that fighter jets were seen fly low over the capital.

Attending the 16th summit of the African Union in Addis Ababa, Ethiopia, UN Secretary General Ban Ki-moon said that demonstrations must be done in a nonviolent and peaceful way and leaders should listen attentively to the voice of their people.

Ban said the United Nations is closely monitoring the situation in Egypt, and stressed that the Egyptian authorities should listen to its people's voices, their aspiration for better life, social and economic development.