Question: How many bombs were used in the attack that killed Tim and Jonathan Ball?
Sentence (from "The Tim Parry Johnathan Ball Foundation for Peace"): It was formed in 1995 by Colin and Wendy Parry, following the loss of their 12-year-old son Tim and 3-year-old Johnathan Ball in the 1993 Warrington bomb attacks, which were perpetrated by the Provisional Irish Republican Army.
Relevant evidence: Yes