The spiritual leader and co-founder of the radical Palestinian Hamas group, Sheikh Ahmed Yassin, has been slightly injured in an Israeli air strike on Gaza City.
Sheikh Yassin opposes peace talks with the Israelis
Hamas officials said the wheelchair-bound leader was hurt in the hand and shoulder and that at least 14 other people, including several children, were also injured in the attack.
Witnesses said a bomb - reportedly dropped by an Israeli F-16 fighter jet - hit the house of an academic and Hamas activist, Marwan Abu Ras, while Sheikh Yassin and other Hamas leaders were there.
Abu Ras said the explosion destroyed the top floor of his house.
The Israeli military confirmed the incident, saying they attacked a building where the Hamas leadership was meeting "to plan future terror attacks against Israelis".
The military also vowed to continue waging "relentless war against Hamas".
Sheikh Yassin later told a crowd of supporters that "the Israeli people will pay a dear price for this crime", Reuters news agency reported.
The Palestinian Foreign Minister, Nabil Shaath, denounced the Israeli strike as "premeditated murder", which would have "a very serious effect on the peace process".
The Israeli attack came shortly after the European Union had agreed to put the political wing of Hamas on its blacklist of terrorist organisations.
The EU is now expected to freeze the assets of Hamas and could prosecute the group's activists.
Hamas officials said the bomb struck the building just moments after Sheikh Yassin and his assistant Ismail Hanieh had left after hearing the approaching Israeli aircraft.
The building was in a densely populated area
"We heard a loud noise and then everything went black and then red before my eyes," Mr Ras was quoted as saying.
Witnesses said Sheikh Yassin was rushed away by his bodyguards in his car.
According to some reports, he was treated at Gaza City's Shifa Hospital.
As the wounded were rushed to hospital, hundreds of supporters of Hamas gathered outside and chanted demands for revenge attacks against Israel.
Hamas officials - speaking through a loudspeaker at the hospital - and threatened to assassinate Israeli Prime Minister Ariel Sharon in a revenge attack.
"Sharon, your head is now wanted," the crowd chanted.
Israel has killed at least 11 Hamas militants and four civilian bystanders in helicopter missile strikes in Gaza since 21 August.
Two days before that, a suicide bombing killed more than 20 people on an Israeli bus in Jerusalem.