Karachi, Pakistan - At least five people have been killed in an explosion at a mosque in the southern Pakistani city of Karachi.
Eighteen people were wounded, four seriously, in the blast at the Shi'ite Mandinatul Ilm mosque, hospital officials said.
The attack comes just days after a suicide bombing at a Muslim festival in the Pakistani capital Islamabad killed at least 19 people and wounded dozens more, mostly Muslims from the minority Shi'ite sect.
Pakistan has been troubled by religious violence since it joined the US-led war on terrorism after the September 11 attacks in 2001.
More than one hundred people have been killed in tit-for-tat attacks by majority Sunni Muslim militants and Shi'ite militants in the past year.