A Palestinian militant leader has died of his wounds, hours after a car bombing in southern Lebanese city of Sidon that also killed his brother.
The force of the blast left the car a twisted wreck
The bomb went off in a nearby car as they were walking in the coastal city, killing Nidal Majdoub instantly.
Mahmoud Majdoub, leader of the Islamic Jihad group in southern Lebanon, died in hospital a few hours later.
Jihad officials blamed Israel for the killing. Israeli military sources said they did not have any information.
Unlike the other main militant Palestinian factions, Islamic Jihad has not joined an unofficial ceasefire in Israel and the occupied territories.
About 400,000 Palestinians live in Lebanon, refugees since 1948 from homes in what is now Israel and their descendants.
Islamic Jihad has been behind most of the Palestinian attacks against Israel since the truce was declared in February 2005.
A representative for the group in Beirut, Abu Imad al-Rifai, told al-Jazeera TV that it had been the second attempt on Mr Majdoub's life, and he blamed Israel for both attacks.
A local resident said he saw black smoke billowing from a car after he heard the explosion. After running down six flights of stairs, he said he "found the two bloodied men lying on the ground in front of the car... and within minutes an ambulance picked them up".
Israel has repeatedly targeted Islamic Jihad officials in the Gaza Strip and West Bank with deadly missile strikes and arrest raids.
Reports say Mahmoud Majdoub, his wife and infant son, and another passer-by were wounded in a car bomb in 1998.
That attack was blamed on Israel as well, but correspondents say leading members of Palestinian groups have also been assassinated in inter-Palestinian feuds.