Hamas has vowed revenge for the killing of its leaders.
In a rare interview on 19 April, Tim Sebastian flew to Beirut to talk to Khaled Meshaal, the overall leader of Hamas. This interview was recorded before the death of his colleague, Abdelaziz Rantissi.
After the killing of the spiritual leader of Hamas, Sheik Yassin by Israeli forces in Gaza, Khaled Meshaal, the organisation's overall leader, said Hamas now had the right to hunt down any senior Israeli leader in revenge.
Meshaal himself survived an attempt on his life by Israeli agents in 1997.
Hamas has deliberately strengthened its leadership outside the occupied territories since the killing of Sheik Yassin.
In a rare interview he travelled to Beirut to talk to Tim Sebastian.
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