"Twenty tunnels are partially back to work since Sunday out of the 250 tunnels still closed because of Egyptian security measures on borders," a source in the Hamas borders and tunnels authority told Anadolu Agency.
The operational tunnels are being used to smuggle food, fuel and construction materials into Gaza.
About 40 to 50 trucks of cement are smuggled through the tunnels per day, down from 300 to 400 trucks daily.
The source said about 3 million litres of fuel were smuggled through the tunnels in the past five days.
Egypt has launched a security crackdown in Sinai in the run up to mass protests that led to the army's removal of elected president Mohammad Morsi.
The security crackdown has caused a fuel shortage in Gaza and doubled the prices of building materials.
An owner of a fuel-smuggling tunnel says the army reinforcements are disrupting the smuggling operations through tunnels.
"The smuggling operations are going slowly and at high risks because of the big security reinforcements at Gaza borders," he told AA.
He said army troops destroyed four fuel pumps and a tanker inside a smuggling tunnel on Friday.
But he said eight tunnels now operate to smuggle construction materials into Gaza, out of 50 tunnels.
"We are now able to smuggle 400 tons and cement and 400 tons of gravel, from more than 2,000 tons in the past," he said.
Another tunnel owner agrees: "Smuggling is being done with great difficulty and at high risks to the life of workers because of army attacks on the tunnels".
Underground tunnels are a lifeline for the Palestinians living in Gaza, which has been under an Israeli blockade since 2006.
"Thank God, I think no one is thinking of unleashing a large-scale conflict with Russia. I want to remind you that Russia is one of the leading nuclear powers."
In a statement, the U.S. Embassy said the arms shipments started on Thursday and so far had included 480 anti-tank guided missiles, more than 1,500 M16-A4 rifles, and "many mortars".
The rallies coincide with rival protests staged by thousands of Shiite Houthis
Human rights watch calls decision to dismiss charges against former leader for role in 2010 violent crackdown of protesters serious setback for accountability.
Fighters from the self-styled 'Islamic State' (IS) have demonstrated knowledge of the CIA's waterboarding interrogation method.
Senegal, a major hub for the business and aid community in West Africa, became the region's fifth country to confirm a case of Ebola
Mosques, monasteries, churches, tombs, shrines and archaeological sites were all under threat by rebels from the self-styled 'Islamic State' (IS) militia
The murder of U.S. journalist James Foley almost two weeks ago by a man suspected of being a British national has prompted demaands for extra security measures
The number of Syrian refugees left stranded by their country's ongoing civil war has surpassed 3 million, and 6.5 million are also displaced within Syria
Sharif said he had nothing to do with the army's decision to step into the conflict. But the army swiftly denied this, saying it had been specifically instructed by the government to step in.
About 80 U.N. soldiers from the Philippines remain locked down in two camps on the Syrian side of the frontier
A spokesman for Libya's renegade general Khalifa Haftar denied the claim that one of his planes was shot down by the Benghazi Revolutionaries Shura Council.
Ukrainian officials say public support for joining the alliance is mounting, and they have increasingly spoken about needing the formal protection of the alliance.
A crowd of young men, some armed with clubs and knives, set up barricades across the southern city and threatened to attack the hospital before security forces moved in to restore order
South African Magistrate Stanley Mkhari said four men - two Rwandan and two Tanzanians - were guilty of the first count to commit murder four years ago
Jimmy Carter, who is 2006 wrote a book that criticized Israel for enforcing a worse system of Apartheid than that which was witnessed in South Africa recently blamed Israel again for deliberately starting the current war with Hamas.