Egyptian security officials say they have seized two tons of explosives headed to the Sinai Peninsula from Cairo.
They say the explosives were seized Saturday in the main Suez Canal transport tunnel that links Egypt to the Sinai.
The truck driver is being questioned.
The officials spoke on condition of anonymity in line with regulations.
Lawlessness has been rife in Sinai since the ouster of longtime ruler Hosni Mubarak in February 2011.
In the past two years, Egypt's Interior Ministry has confiscated hundreds of weapons smuggled from Libya. Officials say some of these weapons are then smuggled into Gaza.
Sinai's Islamist militants also have benefited from the deterioration of security in the area and have begun to launch bolder attacks against the police and military.
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