Mr Samir Abu Zeid was killed along with his daughter Inas (7), and his son Suliman (5), in a Sunday night explosion at their home in Rafah, at the southern foot of the Gaza Strip.
That much is undisputed. But the circumstances of their deaths were being furiously debated yesterday - with potentially vicious consequences.
Mrs Samia Abu Zeid, the dead man's wife, insisted that her husband and children were the victims of an Israeli missile attack. Mr Abu Zeid was a prominent intifada activist, a founding member of the local Popular Resistance Committee, which united various Palestinian factions in violent opposition to Israel in the Rafah area, one of the intifada's hottest locations.
"He was on the Israelis' 'wanted list' for a long time," said Mrs Abu Zeid.
"They wanted to be rid of him." The radical Hamas movement, which has carried out a string of suicide attacks inside Israel, also charged Israel with responsibility, and vowed to the avenge the deaths with more such strikes, asserting that its suicide bombers were already poised inside Israel.
"We have mujahideen (fighters) inside the Zionist entity awaiting the signal to explode like an earthquake and turn the Zionists to pieces," shouted a member of the Hamas wing to the thousands who attended the funerals yesterday.
But Israel, which publicly acknowledges maintaining a policy of "targeting" those it claims are behind attacks on Israeli targets, and which has generally indicated in recent weeks when such hits have been carried out, adamantly denies that its forces were involved.
Initially, Israeli military sources suggested that the three family members might have been hit by a Palestinian mortar shell, but later officials said they had "unequivocal" information that Mr Abu Zeid had killed himself and his children in a "work accident" - the premature detonation of explosives that he was preparing.
Israeli military officials would, of course, have every interest in trying to escape responsibility for an attack in which young children were killed, the more so given that, also on Sunday, its forces shot dead a Palestinian teenager in nearby Khan Younis, and two Palestinian men in the Nablus area - one at a roadblock and another during an exchange of fire in which, Palestinian sources say, he played no part.
But Palestinian sources said Mr Abu Zeid was a bombmaker. And an Associated Press journalist who visited the Abu Zeid home reported that it bore no evidence of a missile hit.
Although one neighbour asserted that he saw a missile heading toward the home, the news agency reported that, "There were no signs of impact on a wall or a roof," no tell-tale crater on the ground, and that the fatal explosion "appeared to have taken place inside the yard" - findings that could support the Israeli "work accident" assertion.
Since neighbours said that policemen from the Palestinian Authority removed evidence from the house later on Sunday night, a conclusive account of these three deaths in Gaza may never be obtained. But after 11 months of bitter conflict, with many on both sides more than ready to believe the worst of each other, there may yet be violent repercussions.