An Israel Navy ship clashed on Tuesday with a small boat carrying international activists with aid destined for Gaza, an Israeli Foreign Ministry spokesman said.
There were no reported casualties from the incident involving the small cabin cruiser "Dignity" that sailed from Cyprus late on Monday.
Israel has declared the coastal territory a closed military zone and said the Free Gaza Movement boat would not be permitted to dock.
Yigal Palmor, a spokesman for Israel's Foreign Ministry, said the boat failed to respond to Israeli naval radio contact, and that an Israeli vessel "clashed with the ship."
Free Gaza Movement told Reuters their boat, carrying 3.5 tons of medical aid with 16 people aboard, was rammed and shot at while in international waters about 70-80 miles off Gaza by Israeli naval vessel.
Palmor denied there had been any shooting although the two ships made "physical contact." He said no one had been hurt and that the Israeli ship escorted the aid boat back to Cypriot territorial waters.
Israel has declared areas around the Gaza Strip a "closed military zone" after it launched an aerial offensive in the coastal territory on Hamas targets on Saturday, in which 345 Palestinians have been killed.
Free Gaza Movement said their boat was safe, but had sustained damage.
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