The sources said only about 10 percent of the 1,500 tunnels that link the Gaza Strip to Egypt's Sinai Peninsula were operating, Middle East Newsline reported. They said Gazans preferred the cheaper and better-made products from Israel rather than from Egypt.

As a result, Hamas has suspended shipments of Israeli diesel fuel to the Gaza Strip. Until this year, Israel had been supplying 100,000 liters of diesel to operate the electricity generation station in Gaza.

"Hamas prefers to smuggle the fuel from Sinai because it supports the tunnel operators close to the regime and, of course, it's much cheaper than from Israel," the source said.

The sources said Hamas wants to maintain the smuggling tunnels as a source of revenue for the Islamic regime. They said Hamas receives fees from each shipment from Sinai, believed to have increased amid the unrest in Egypt.

Over the last week, at least eight Hamas operatives escaped Egyptian prisons. One of them was identified as Ayman Nofal, arrested in 2008 on charges of plotting bombing attacks in Egypt, and who arrived in the Gaza Strip on Feb. 5.