GAZA CITY, Gaza Strip (AP) - Palestinian militants bombarded southern Israel with rockets and mortars on Saturday, part of a new outburst of violence that threatens fragile Egyptian efforts to broker a truce in the Gaza Strip.

No one was seriously hurt in the attacks. The flareup in violence began Friday when Hamas militants fired mortar shells that killed a 48-year-old Israeli man while he was gardening at his home near the Gaza border. Israel retaliated with airstrikes that killed five militants from Gaza's ruling Hamas movement.

Israel said militants fired 21 rockets and four mortars by late Saturday afternoon. A house in the rocket-scarred town of Sderot took a direct hit, and rockets landed near a religious seminary and in the courtyard of a local college.

Palestinian militants frequently fire crude rockets and mortars into southern Israel from Gaza, killing 14 civilians in all since late 2001. The attacks often provoke harsh Israeli airstrikes and ground incursions, although hostilities have ebbed since more than 120 Palestinians were killed in a flare-up of violence two months ago.

Egyptian intelligence chief Omar Suleiman is expected in Israel early next week to discuss his efforts to wrest a cease-fire from the two sides. It remains unclear whether he will be able to forge a deal.

In related news, the mayor of a southern Gaza village said Israeli troops had fired flares at farmlands, setting ablaze several acres (hectares) of wheat and cucmbers.

The Israeli military said it would look into the report from the village of Khouza. Militants frequently use the area to fire rockets and mortars at southern Israel.

Also in Gaza, officials said they switched off all three turbines that had been generating electricity for hundreds of thousands of Gazans. Energy official Kaanan Obeid said Israel - the sole supplier of Gaza's fuel - hadn't provided enough diesel to run the power plant.

Ninety percent of Gaza City, the territory's biggest city, was plunged in darkness Saturday night, Obeid said.

Israel has limited its rations of fuel and other supplies to Gaza in an attempt to pressure militants to stop firing rockets at nearby Israeli towns.

An Israeli military spokesman said Saturday that Israel didn't deliver as much fuel as planned to Gaza this week because Palestinian militants attacked the crossing Israel uses to deliver it. He said he did not know when fuel supplies to the power plant would resume.

The plant has shut down before, citing fuel shortages, but Israel delivered fuel the following day.

It was not immediately clear if the privately owned power station had actually run out of fuel Saturday or whether it was shut down to pressure Israel to deliver fuel.

Israeli government spokesman David Baker denied Israel was to blame for the blackout.

"Israel continues to supply fuel and vital humanitarian goods to Gaza," Baker said. "There is no logical reason for this fuel plant to be shut down. This is another example of Hamas orchestrating an artificial crisis for its own political aims and once again Hamas is showing a complete disregard for the welfare of the Palestinian people."

In recent months, Gazans have commonly spent four to six hours of every day without electricity because of the fuel shortages. Many people used to rely on small generators to fill the breach, but fuel for these units also has become exceedingly scarce, leaving most people to resort to candles. It is widely believed that Hamas has diverted some of the fuel Israel has delivered for its own use.

Meanwhile, in the West Bank, nine Palestinians were shot in clashes with Israeli troops after youths hurled rocks and firebombs at Israeli army jeeps, medics said.

A military spokeswoman said the violence broke out after Palestinian youths in the West Bank town of Jaba noticed that a military jeep had broken down. The attacks continued after reinforcements were called in for the disabled patrol, and troops responded by firing live rounds in the air, rubber-coated bullets and tear gas, she said.

Palestinian security recently beefed up its forces in Jenin district to try disarm Palestinian militants who organize attacks on Israel. Palestinians say Israeli army incursions into the area hinder their job. The issue has become a major point of contention in peace talks between the two sides.