Palestinian Authority blames Hamas for mishandling explosives.

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Israel seals borders, blast kills 15 Palestinians

JERUSALEM (AP) — The Israeli military on Saturday sealed off the West Bank and Gaza Strip in response to Palestinian rocket attacks.

MahmudHamsi, AFP/Getty Images
A vehicle explodes in the Jebaliya refugee camp just before Hamas leader Ismail Haniya was to address the celebratory crowd.

At a Hamas rally Friday, a truck filled with masked militants and homemade weapons exploded, killing at least 15 Palestinians and wounding 80 — including children — bringing a grisly and terrifying end to one of the last gatherings by armed groups celebrating Israel's Gaza pullout.

Mishandled explosives apparently caused the blast, which came a day before an agreement by militants not to publicly parade weapons is to take effect.

Hamas said six militants were killed, including Jihad Shaleal, head of the group's military wing in Jebaliya. Hamas blamed Israel, but the Israeli military denied any connection. Palestinian security officials said the blast was an accident.

The explosion came in the middle of the celebration. The militants are extremely popular with young Palestinians, and teenagers surrounded the pickup before the blast, said Abu Rashad, who was just a few feet away. He said three militants with two homemade rockets were in the truck's bed, and three or four other militants rode inside.

Hamas swiftly claimed Israeli aircraft had targeted the militants with a missile. "We will avenge the blood of our martyrs," said Nizar Rayan, a Hamas leader.

But Palestinian officials said the explosion was set off by the mishandling of explosives. The Interior Ministry issued a statement calling on Hamas "to shoulder its responsibility for these ... explosions instead of making accusations against others."

An accidental explosion would be only the latest in a string of deadly mishaps for militant groups in Gaza.

A Hamas weapons warehouse exploded this month in Gaza City, killing six people. Hamas claimed it was an Israeli attack, but Palestinian security forces found the blast was an accident caused by the militants.

During an Islamic Jihad rally at the abandoned Jewish settlement of Netzarim last week, a gunman died after accidentally shooting himself in the head.