Hamas's military wing accuses Israel, but the army denies involvement.
Six Palestinians have been killed in an explosion in the Gaza strip.
The cause of the blast in Deir al-Balah was not immediately clear, but the Izzedine al-Qassam Brigades, military wing of the Hamas militant group, blamed Israel.
The Israeli military has denied involvement.
A Palestinian source quoted in Israeli newspaper Haaretz said the six dead appeared to be Hamas members and that the blast may have been caused by the handling of explosives inside a building.
Tensions in the region are high since demonstrations along the Gaza-Israel border erupted more than a month ago, often descending into clashes between protestors and the Israeli military.
