(dpa) - Palestinian militants continued their rocket attacks from Gaza Friday, as Israel overnight began implementing a new punitive measure - a symbolic, but gradual cut in electricity to the strip.
Four rockets landed in Israel's southern Negev desert close to the Gaza border Friday morning, am Israeli military spokeswoman said.
Israel began implementing the new, but long-announced measure after Hamas militants launched more than 60 rockets and mortar shells at it in the last three days, and after Israel's supreme court authorized it last week.
The supreme court rejected a petition by Palestinian and Israeli human rights groups, saying the step violated international law.
On Thursday evening, Israel's electricity company cut power on one of 10 lines supplying Gaza by 5 per cent.
The cut constitutes slightly over half a Megawatt, or 0.5 per cent of the 124 Megawatts Israel supplies to Gaza every day.
Israel has threatened to cut a second line by another 5 per cent next week, and third line by yet another 5 per cent in two weeks, if the rocket attacks continue.
"This is part of the continued disengagement from the Gaza Strip," a Israeli Defence Ministry spokesman said, referring to the 2005 "disengagement" plan in which Israel pulled its permanent military presence and settlements out of the strip.
The US State Department said it was "concerned" about the humanitarian situation in Gaza. Deputy Spokesman Tom Casey said the US respected Israel's right to defend itself against the rocket attacks, but added, "At the same time, we don't want to see Israel do anything that would worsen the humanitarian situation for the people of Gaza."
Human Rights Watch issued a statement in New York charging the electricity cut violated the laws of war.
Local Israeli and Palestinian human rights groups too condemned the move, but pointed out that Israel's June 2006 airstrike on Gaza's only power plant, and subsequent reductions in the delivery of industrial diesel to it, had had a larger impact.
The power plant, which runs on industrial diesel, supplies more than half of Gaza's 1.5 million residents, but currently generates only 55MW a day, less than the about 80MW it would be able to generate if it received more fuel, and than the some 100MW it generated at full capacity before the 2006 strike.
Israel launched the airstrike after Hamas led a cross-border raid on a military outpost near Gaza and abducted a soldier who is still being held captive in the strip.
It also imposed a stringent blockade, which was tightened further after the radical Islamic Hamas movement seized sole control of Gaza last June.
Before the 2006 escalation, the Gaza Strip received some 230MW in electricity a day - 124MW from Israel, 100 from its own power plant and another 17 from Egypt. The 45MW cut in output from the power plant has therefore meant a reduction of nearly 20 per cent.
And residents of Gaza City and its surroundings who are being supplied by the powerplant have faced power blackouts of up to eight hours a day.
In its January 30 decision, Israel's supreme court said the state must guarantee the basic humanitarian needs of Gaza's civilian population, but said it had no obligation to supply it beyond that.
Hamas has fired more than 60 rockets and mortar shells at Israel since Tuesday afternoon, when an Israeli airstrike on their station in southern Gaza killed seven Hamas policemen.
Since then, another seven Palestinians, including six militants, five of them of Hamas, and a civilian school teacher, have been killed in Israeli airstrikes and ground fighting in northern Gaza.
The Israeli military said it exposed two semi-underground rocket launching sites during the ground incursion into northern Gaza.