Security tight following Egypt clashes

Riot police stand guard on debris-ridden streets near St. Mark's Coptic Cathedral in Cairo.

On Sunday, at least one person was killed and more than 80 injured in clashes here.

The trouble erupted after the funeral for four Coptic Christians killed in earlier sectarian violence.

The four Christians and a Muslim died on Friday just north of Cairo during a shootout between the two communities - bringing the total death toll of recent clashes to six.

The violence has left residents calling for unity, regardless of their religion.

(SOUNDBITE) (Arabic) EGYPTIAN MAN, MAGDI WADIA, SAYING:

"This type of thing has never happened before and we have never seen the country reach this state of affairs. And this will not only affect Christians and Muslims but the whole situation in Egypt. And this is wrong - we are one people and one country."

Christian-Muslim tensions have increased since the overthrow of president Hosni Mubarak in 2011.

President Moha