A bomb exploded on a bus in northeast Pakistan on 28 April, killing 37 people and injuring about 30. Most of the passengers were travelling home to the city of Pattoki, 70 kilometres from Lahore, to celebrate the Muslim festival Eid al-Adha.

No group has yet claimed responsibility for the explosion. Prime Minister Benazir Bhutto, visiting Lahore on 29 April, blamed unspecified 'terrorists', describing the act as 'subversion aided by foreign elements'.

Islamabad has often accused India of sponsoring sabotage in Pakistan as a response to its political support for militants fighting Indian rule in part of the disputed Kashmir region.

The bomb follows earlier blasts, also in the Punjab region. An explosion at a charity hospital in Lahore, on 14 April, killed six patients, and in central Punjab, a bomb at a cinema on 26 April injured 12 people.