|Israel said it began the shelling in response to rockets fired across the border from Gaza [GALLO/GETTY]
Israeli shelling has killed three Palestinians in the Gaza Strip, medical workers and witnesses say.
Hamas security and medical officials said two of the Palestinian killed on Sunday, in Beit Hanoun near the Israel-Gaza border, were farmers.
"Ibrahim Abdullah Abu Saeed, a caretaker at a a farm, aged 91, and Ismael Walid Abu Audeh, 20, were killed on Sunday by fire from an Israeli tank," Adham Abu Salima, a spokesman for local medical
services, told AFP news agency.
Shortly after, Hossam Khaled Abu Saeed, the farmer's 17-year-old grandson, also died of wounds sustained in the incident, close to the flashpoint Gaza-Israel border, a medical source said.
A spokeswoman for the Israeli army confirmed the shooting, saying that troops "opened fire at a group of terrorists preparing to fire an RPG [rocket-propelled grenade]" at Israel.
She added that the incident was the second one at the border on Sunday and that earlier troops had fired warning shots at a group of men approaching the frontier fence.
Earlier on Sunday the Israeli military reported that a rocket fired from Gaza struck Israel without causing any casualties or damage.
It said at least seven rockets or mortar rounds have hit Israel in the past week. On Friday Israel launched a series of reprisal air raids, mostly targeting smuggling tunnels, that wounded two members of the Hamas security forces.
The number of rocket attacks on Israel declined sharply following its massive 22-day Gaza offensive in December 2008 and January 2009, and Hamas has taken steps to rein in the attacks, believed to be the work of rival factions.
However, according to the military more than 100 rockets or mortar rounds were fired into southern Israel since the start of 2010.