Armed assailants opened fire on a mosque belonging to a small Muslim sect in eastern Pakistan this morning, killing at least eight people and wounding 19 others.

Pakistani security officials said today they foiled new terror attacks with the arrest of the head of an al-Qaida linked extremist group accused of killing scores of minority Shiite Muslims.

Police in Pakistan have found a letter from the purported chief of a Sunni Muslim militant group claiming responsibility for this week’s bombing at a Shiite mosque and a shootout in Karachi that left five people dead.

Dozens of stone-throwing Muslim youths set fire to shops in the Pakistani city of Karachi today as sectarian unrest rumbled on despite a citywide shutdown called by a hardline Islamic alliance to protest against violence that has left 12 dead this week.