Premise: He died in a ferryboat accident on Lake Victoria just a few days after Bin Ladin arrived in Jalalabad, leaving Bin Ladin with a need to replace him not only in the Shura but also as supervisor of the cells and prospective operations in East Africa.

Hypothesis: After his untimely death, Bin Ladin was forced to replace his roles in the Shura and in supervising cells in East Africa.
Relation: entailment