Four Palestinian militants from Islamic Jihad were killed in an apparent accidental explosion near the Gaza-Israel border on Saturday, the group said.
Islamic Jihad's armed wing, in a statement, said four of its fighters had been killed during "preparations", without giving further details.
The men died when a tuk tuk vehicle exploded a few hundred metres (yards) from the border with Israel, an AFP correspondent at the scene said.
Islamic Jihad is an ally of Gaza's Islamist rulers Hamas.
The group, which is supported by Iran, has fought alongside Hamas against Israel in multiple wars, most recently in 2014.
The explosions comes a day after a third Friday of protests along the Gaza-Israel border.
Thousands gathered to call for a return to their historic homelands in what is now Israel.
One person was killed Friday as Israeli forces along the border fired at stone-throwing protesters.
*This story was edited by Ahram Online.