Two armed Shias stand guard in Sialkot. (AFP)

Sialkot (Pakistan), Oct. 2 (Reuters): Angry Shias set vehicles and the mayor?s office on fire in Pakistan?s eastern city of Sialkot today after a funeral procession to bury victims of a suicide bomb attack that killed 30 people.

Security was beefed up throughout Pakistan after the suicide bomber detonated the device when hundreds of worshippers from the minority sect were in the Zainabya mosque for Friday prayers.

No one has claimed responsibility for the attack in which more than 50 people were wounded, but suspicion is expected to fall on Sunni groups, which have carried out similar attacks on Pakistan?s Shias in the past. ?The situation is very tense in the city,? a resident said.

The funeral passed off peacefully until the end, when some 100 angry men went on the rampage, burning the mayor?s office, setting fire to parked vehicles and stoning bank buildings and damaging offices in the courthouse.

A mob had set fire to a filling station and burnt two police cars yesterday.

President Pervez Musharraf said the attack ?clearly shows that terrorists have no religion and are enemies of the mankind?.

Earlier, mourners gathered at the bombed mosque to chant incantations praising Allah and the 8th century founders of the Shia sect before joining thousands of their co-religionists in a funeral procession to bury nine of the victims. Sobbing mourners carried black banners and beat their chests in a traditional display of grief.

Some shouted: ?Down with Pervez Musharraf? and ?Down with America?.

Bodies of most of the victims were taken to their native towns and villages for burial.

Local traders announced a two-day closure of shops in Sialkot to protest against the killings, while police were on alert for any sectarian backlash.

In the southern port city of Karachi, a scene of major sectarian violence in recent years, additional police were deployed to guard mosques and Shia religious centres that were the targets of a spate of attacks earlier this year.

In the capital, Islamabad, police checked cars and trucks on main roads and around neighbourhood markets.

No one has claimed responsibility for the bombing but the information minister has said it might be retaliation for the killing last Sunday of the most wanted Pakistani militant, Amjad Hussain Farooqi.

Seen as the main link between Osama bin Laden's al Qaida and local militant groups, Farooqi was a key suspect in two assassination attempts on Musharraf last December.

Sunni extremists were blamed for a series of attacks on Shia mosques in Karachi earlier this year. Shias account for 20 per cent of Pakistan's 150 million people, and Sunnis almost all of the rest. Christians and other minorities account for five per cent.

Some Sunni groups have forged closer links with the al Qaida network amid anger over Musharraf?s support for the war on terror.