The circumstances of how the Palestinian fisherman was killed were disputed. The Israeli army said he fired at a naval ship, but Palestinian security officials said the ship, unprovoked, fired at a group of fishermen.
The army said the Palestinian boat entered an off-limits zone early on Saturday from the direction of Egypt and did not respond to warning shots fired from the naval vessel.
Shots were fired from the boat and from the shoreline at the Israeli vessel, the army said. The navy ship fired back, sinking the boat.
Palestinian security officials said the Israeli navy ship fired at several fishing boats without provocation. They said the fishermen were in an authorised area and that no warning shots were fired.
Sayyid Abu Libda was killed by
Late on Friday, in a separate incident, Israeli troops identified three Palestinians trying to climb the barrier separating Israel and Gaza. Soldiers shot the three, and they were removed by Palestinian medics.
Palestinian security officials said Sayyid Abu Libda, 15, was killed and the two others were wounded. The officials said the three teenagers were mentally retarded and were trying to enter Israel to find work.
On Saturday, three home-made Qassam rockets were fired into southern Israel from the Gaza Strip on Saturday without causing any casualties or property damage, an Israeli army spokeswoman said.
The army responded with artillery fire on an uninhabited area near Bait Hanun, in norther Gaza, also without causing any casualties.
Two of the rockets hit near a kibbutz in Carmilla, south of the city of Ashkelon, and the third near Nativ Ha-Assera.