The Izzedine al-Qassam Brigades said it had broken last November's ceasefire agreed upon by Hamas and Israel "in reaction to the continued Zionist crimes against our people in the West Bank and Gaza Strip".
Today's attacks are a reaction to the deaths of nine Palestinians killed in clashes with Israeli troops over the weekend, as well as a lack of progress in a prisoner exchange for captured Israeli soldier Corporal Gilad Shalit – taken hostage last June.
The rocket strikes come as Israelis commemorate Yom Ha'atzmaut – the country's independence day – for the 59th time.
Yesterday Israeli prime minister Ehud Olmert signalled that the Jewish state would not repeat "mistakes made in the past" by releasing Palestinian prisoners who then went on to attack Israel.
Israel retaliated to today's Izzedine al-Qassam Brigades attacks with helicopter gunfire on the Gaza border.
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