Islamabad: At least 18 people were killed and 40 injured when a suspected suicide bomber blew himself up in a Shiite mosque packed with worshippers during Friday prayers today (Oct 1, 2004) in Pakistan's industrial city of Sialkot, hours after President Pervez Musharraf returned home from his high-profile foreign trip.

The explosion that ripped through the building occurred 1.30 pm local time at the Mistri Abdullah Imambargah mosque in the eastern Sialkot city, 160 kms north of Lahore, in Punjab province, when hundreds of worshippers were listening to the sermons by the Imam, reports reaching in Islamabad said.

A district police official told state-run PTV that an unidentified person with a briefcase had entered the mosque after which the blast took place.

Police suspected that he was a suicide bomber and was carrying explosives in the briefcase.

The blast, which created a one-and-half feet deep hole, took place five days after Pakistani security forces killed one of the most wanted al-Qaeda operatives Amjad Farooqi in a shootout.

Information Minister Sheikh Rashid said the blast was an attempt by the extremist groups in the country to tarnish the positive impression being created by Musharraf to bring in foreign investment.

Musharraf, who returned from his visit to the US, the Netherlands and Italy late last night, said that about 100 al-Qaeda terrorists were killed during a recent military operation in tribal areas near Afghan border.

"Every time the President concludes a successful visit abroad to create a positive impression of Pakistan and canvass for foreign investment in Pakistan, these extremist elements try to spoil his efforts," Rashid told TV networks.

While Musharraf made fervent appeal to foreign businessmen to invest in Pakistan, these extremists elements wanted to destroy the image of Pakistan, he said.

An angry mob attacked police after the mosque blast and the additional police were sent to restore peace. Some of the protestors also burnt a police motorcycle.

Police in the past blamed Sunni extremist group Lashkar Jhangvi, which was banned, for such attacks in Shiite mosques.