A militant with the armed wing of Gaza's ruling Hamas movement died in Gaza City on Wednesday after the car he was travelling in exploded, Palestinian medical sources said.
There was no accusation against Israel, prompting suspicions it was a "work accident," a euphemism for the accidental detonation of explosives held by militants.
Medics named the victim as Ayman al-Shufra, a member of the Ezzedine al-Qassam Brigades, and said two other Palestinians who had also been in the car with him were wounded.
The blast, which took place before dawn, hit an SUV in the Tel al-Hawa neighbourhood of western Gaza City, critically wounding Shufra, who died several hours later.
The Israeli military said it was not involved in the incident, with a spokeswoman saying it was "not related to any IDF (Israel Defence Forces) activity."
In a separate incident later on Wednesday, a Popular Front for the Liberation of Palestine militant was seriously wounded in an explosion.
According to medics and eye witnesses, the explosion took place at the PFLP training site in the southern Gaza Strip city Rafah.
A spokeswoman said the Israeli army also had had nothing to do with that explosion.