Two explosions on Thursday hit an Egyptian pipeline, halting supplies to Israel and Jordan, officials and Egypt's security services and state media said.
It was the seventh time it has been attacked by militants this year.
The first blast on Thursday occurred around 1:00 am (2300 GMT Wednesday) 40 kilometres (25 miles) west of the town of El-Arish in the north of the Sinai peninsula, a security source said.
A second unexplained explosion took place near a pumping station in the same sector, the official news agency MENA said, adding that the army was deploying in the region.
In Israel, Maya Berdugo, spokeswoman for the infrastructure ministry, said: "Israel is making up for the shortage caused by this new attack on the Egyptian gas pipeline by drawing more from Yam Tethys."
She was referring to an offshore reserve which is reportedly depleting faster than predicted.
In the Jordanian capital Amman, an official, who asked not to be named, said: "Deliveries of Egyptian gas to Jordan have been interrupted following the pipeline attacks."
Egyptian state television aired images of a raging fire at the site of one of the blasts. It said the fire was under control.
The pipeline, which carries gas through the Sinai and on to Jordan and Israel, had already been attacked six times since former president Hosni Mubarak was toppled in February.
Witnesses said they had seen armed men at the scene of the first blast, the security source said. He did not know if there had been any victims.
MENA, also quoting witnesses, said a blaze could be seen after the explosion. Witnesses said that before the blast two cars crowded with armed men were seen heading to the pipeline, the news agency reported.
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Previous attacks have also disrupted gas deliveries to both destination countries several times.
Israel said in late October that gas imports from Egypt had resumed after a cut of several months because of the attacks. The pipeline also feeds an industrial area in mid-Sinai, MENA reported.
Egyptian gas also covers 80 percent of Jordan's electricity production demand -- 6.8 million cubic metres a day.
The Jordanian official said that since attacks in February, Jordan had "only been receiving one third of the amount of Egyptian gas needed, that is nearly 2.3 million cubic metres a day."
The cuts amount to "a daily loss for Jordan in the order of $2 million," he said.
Jordan's two main electricity plants, at Aqaba and Rihab, "have stopped using Egyptian gas since April and turned instead to oil and diesel."
Egyptian authorities have on several occasions announced measures to step up protection of the pipeline and try to arrest those behind the attacks.
The most recent attack was on September 27, when one person was injured.
Army experts have also located and defused a number of other devices targeting the pipeline.
Israel generates 40 percent of its electricity using natural gas, and Egypt provides 43 percent of its supplies of the material.
The deliveries to Israel, agreed under Mubarak who was overthrown on February 11, have come under heavy criticism in Egypt. Mubarak's government was accused of selling the gas at a low price.
Mubarak and a business associate face corruption charges for the deal to sell the gas. The oil ministry has said it would revise the contract with Israel to substantially raise the price.
Egypt's Sinai region is particularly security sensitive due to tensions with the Bedouin community living there. Many goods are smuggled to the Palestinian enclave of Gaza through Sinai, which the Israelis also charge is a rear base for militant attacks against its territory.
The military and police launched a sweeping operation in the peninsula in October to uproot Islamist militants believed to be behind the attacks on the pipeline and a police station in El-Arish.