A bomb blast at a religious gathering of Sunni Muslims in Pakistan's southern port city of Karachi today killed at least 47 people and wounded about 100, police and a government minister said.

``It is a big incident,'' Pakistani Interior Minister Aftab Sherpao said in an interview on GEO television.

Riots broke out in Karachi after the blast, and protests and violence spread to other cities of the Sindh province, including Hyderabad and Sukkur.

The blast occurred at about 7 p.m. at Nishtar Park, in the center of the city, where thousands of people had gathered to mark the birth of the Prophet Muhammad, Karachi police official Muhammad Mushtaq said by telephone.

``It is an act of terrorism and difficult to assess now whether it was suicide attack or remote controlled bomb,'' Sherpao said.

Pakistan, a Muslim nation of 160 million people, has had several attacks in recent years, many of them in Karachi. President Pervez Musharraf blames the violence on opponents of his support for the U.S.-led campaign against terrorism. Some of the attacks are attributed to rivalries between the Shiite Muslim minority and the Sunni Muslim majority.

Hanif Billo, the chief of Tehrik Ahl-Sunnat, the Sunni Muslim group that organized the gathering, was among at least 47 people who died in the attack, Sindh's provincial minister Shabbir Ahmed Qaim Khayni in Karachi said by telephone. About 100 were injured. No one acknowledged responsibility for the attack, he said.

People angered by the blast gathered at the site and kept police from entering the park, Mushtaq said. Protesters burned several cars and threw stones at police, he said.

Witnesses Report Arson
Aaj, a private television channel, cited eyewitness reports that angry protesters burned over a dozen vehicles, three gasoline pumps and a movie house.

All markets and shops will be closed on Wednesday to express solidarity with those who were killed and injured in the bomb blast, Atiq Meer, chairman of All Markets Alliance Association in Karachi, said by telephone. The Sindh government also announced all schools will be closed for three days.

Altaf Hussain, chief of the Mutthadia Qaumi Movement, self- exiled and living in London, called for a three-day mourning period and urged people to remain clam.

On March 2, an American diplomat was among four people killed in a car bombing near the U.S. Consulate in Karachi, two days before U.S. President George W. Bush visited the country.

Source: Bloomberg.com