The spiritual leader of Hamas, Sheikh Ahmed Yassin, has denied any direct involvement in attacks by the radical Islamic group against Israeli targets.
Defiant Sheikh Yassin he was not frightened of death
He said on Friday he had "nothing to do with military action".
His statement came shortly after Israel's Deputy Defence Minister Zeev Boim pledged to "eliminate him" saying he was "marked for death".
Mr Zeev was responding to a Hamas suicide attack on Wednesday in which four Israelis died.
Israeli media say the military believes Sheikh Yassin personally ordered the attack at the Erez crossing point from Gaza - Hamas' first female suicide bombing.
On Friday, the wheelchair-bound Sheikh Yassin said:
"Death threats do not frighten us, because we are in search of martyrdom."
There was no indication that he was changing his usual routine in light of the Israeli threat.
'We will find him'
On Thursday, Mr Boim said Israeli security forces were considering resuming their practice of targeting top Hamas officials, adding that Sheikh Yassin topped the list.
"Sheikh Yassin is marked for death, and he should hide himself deep underground where he won't know the difference between day and night," he told Israel Army Radio.
"And we will find him in the tunnels, and we will eliminate him," he added.
Sheikh Yassin has already survived one Israeli attempt on his life.
Last September, an Israeli warplane dropped a bomb on a building in Gaza where he and top Hamas leaders were meeting.
Wednesday's suicide bombing was carried out by Hamas member Reem Raiyshi, a mother-of-two in her early 20s, from Gaza.
Raiyshi eluded security checks by telling soldiers she had a surgical plate in her leg after she triggered metal detectors.
She blew herself up in an office when a female soldier prepared to examine her, killing four soldiers and wounding a dozen civilians.
Hamas, which jointly claimed the attack with the secular al-Aqsa Martyrs' Brigades, said it used a woman suicide bomber to make detection more difficult.