Updated

Egyptian authorities confiscated trucks carrying explosive warheads and a variety of small-arms ammunition smuggled from Libya, security officials said Wednesday.

A flood of weapons from its western neighbor has added to Egypt's security concerns as police have yet to fully return to their duties since last year's uprising. Smuggled weapons often fall into the hands of Islamist militants in the Sinai Peninsula, or pass via underground tunnels to the Gaza Strip, the site of fierce fighting over the past week between Hamas militants and Israeli forces.

The Egyptian officials said authorities seized the pick-up trucks, carrying 108 warheads for Soviet-designed Grad rockets, near Marsa Matrouh, 270 miles (430 kilometers) northwest of Cairo on the Mediterranean coast. Suspected smugglers had fled the scene.

Officials spoke on condition of anonymity because they weren't authorized to brief reporters.

Also on Wednesday in Egypt's troubled northern Sinai region, troops from a multinational observer force fired on protesters demonstrating outside their base against the Israeli offensive in Gaza. Egyptian security officials said that one person was killed and another injured. The 12-nation observer force is part of the peace treaty signed by Egypt and Israel in 1979. American troops make up the largest contingent of the 1,650-strong force.

Libya's revolution last year unleashed a flood of small arms and heavy weapons, including shoulder-launched anti-aircraft missiles, into circulation through the vast Sahara desert of North Africa. Military experts say weapons that cross Libya's porous borders with neighboring Egypt and Sudan could be falling into the hands of Islamic militants.

Hamas and Islamic Jihad militants in Gaza have stockpiled Grad rockets and fired them at Israeli territory over the years, including in the latest round of fighting.