Two Israelis and a Ukrainian were sentenced to life in prison by an Egyptian court on Monday on charges of smuggling a machine gun and ammunition across the Israeli border into Egypt, a court source said.
The Ukrainian and one of the Israelis are in Egyptian custody, while the other defendant was tried in absentia.
Security along Egypt's border with Israel, long a conduit for the smuggling of guns and people, was relaxed after the ouster of former President Hosni Mubarak following a popular uprising in February 2011, as police presence thinned out across Egypt.
The region has been hit by a number of gas pipeline explosions and cross-border attacks.
According to the court that issued the conviction, the Ukrainian, manager of a tourism company in the Egyptian resort town of Sharm el-Sheikh, had ordered the weapon from one of the Israeli defendants, the source said.
The other Israeli, who lived in the southern Israeli city of Eilat, brought the weapon into Egypt at the border at Taba in a cross-shaped wooden crate.
The machine gun and ammunition were discovered when the crate was placed on an explosives detection machine. The weapon was the sort used by police in Egypt's Sinai Peninsula, investigators said.
The captured Israeli has denied knowing the contents of the crate, while the Ukrainian said he had ordered the weapon for personal protection, the court said.
In June, Egypt arrested an American-Israeli on suspicion he was trying to recruit agents and monitor events in the uprising that toppled Mubarak, an ally of Israel and the United States. He was released in October in a prisoner swap that included the release of 25 Egyptians held in Israel.
Egyptian officials say limits on troop numbers in Sinai under a 1979 peace treaty with Israel make it harder to secure the mountainous region.