1.   Black Ice breaks up the system by having each computer monitor itself, which allows it simultaneously to trace perpetrators.

2.   So far, police have failed to trace the perpetrators.

3.   Transport and Communications Minister Suleiman Tejan-Jalloh ordered an official investigation in the dumping and promised stiff punishments if the perpetrators were traced.

4.   Bhutto has strongly condemned the attack and ordered official agencies to mobilise all resources to trace the perpetrators.

5.   No one immediately claimed responsibility for the bombing and police said they had launched an investigation to trace the perpetrators of the attack.