Khaled Mashal
In retaliation for these and other attacks, a decision was reached to target Hamas leaders. According to an Israeli press release, Mossad agents tried to poison chairman Khaled Mashal, who resided at the time in Jordan. The assassination attempt failed and the Mossad agents were captured by the Jordanian authorities. They were later released in exchange for the release of Sheikh Ahmed Yassin, the founder and "spiritual leader" of Hamas who was serving a life sentence in an Israeli prison.