Clashes between Christians and Muslims escalated Tuesday in a day of violent protests in Egypt's capital.
Soldiers fired shots in the air to break up the clashes that broke out south of the capital while people burned tires and smashed parked cars.
Earlier, thousands of Christians demonstrated in two other Cairo locations against perceived persecution by the country's Muslim majority.
Hundreds of Egyptian women demanding equal rights and an end to sexual harassment also were confronted by men who verbally abused and shoved them in a separate protest on Cairo's central Tahrir Square.
Tensions remain high nearly a month after mass protests ousted President Hosni Mubarak.
While the clashes ensued Egypt's armed forces detained the head of the state security services on Tuesday, Al Jazeera satellite television reported.
Protesters last week stormed state security buildings and confiscated documents they said showed evidence of human rights abuses. An army official was not able to immediately confirm the report.
Meanwhile, Sudanese President Omar al-Bashir met with the head of Egypt's Armed Forces Tuesday in Cairo to discuss ways to strengthen economic and political bilateral ties, state media said.
Al-Bashir is the first Arab leader to visit Egypt after former president Hosny Mubarak resigned on February 11.
He met with Field Marshal Mohamed Hussein Tantawi, head of the Supreme Council of Armed Forces, which currently runs the country. They also discussed successive development of events across the region.
"Al-Bashir's visit to Cairo reveals a Sudanese supportive stance for the Egyptian people during such a historical situation," said Sudanese Ambassador to Egypt Abdul Rahman Siral-Khatim, according to the independent daily Al-Masry Al-Youm.
Under Mubarak's rule, Egypt had backed al-Bashir against an arrest warrant by the International Criminal Court issued against him in 2009.
The Sudanese leader has repeatedly defied the indictment, which was issued for his alleged role in directing war crimes and genocide in Darfur.
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