No asylum seekers entering Israel illegally from Egypt have been found to be involved in terror activities, though the Bedouin guides who help them get into the country do pose a security risk, according to the Israel Defense Forces.

Security forces prevented a terror attack on the Israel-Egypt border Monday by thwarting the second attempt in two weeks to place an explosive charge on the border "using the criminal smuggling network in Sinai," an IDF officer told the media.

The Bedouin guides who help asylum seekers and other migrants entering the country illegally are "experts at moving people, merchandise and illegal foreigners, and at hostile actions," a senior IDF officer in the Southern Command said in a press briefing last week.

He said weapons have become prevalent when people and goods are smuggled in and that the guides are adept at traversing the border region's desert terrain.

Since 2005, sources in the IDF said, the smuggling has been motivated not only by financial gain but also by anti-Israel ideology, possibly because of the influence of fundamentalist Islam.

But the IDF has not substantiated any allegations that the illegal immigrants themselves themselves are involved in terrorism, despite warnings by several politicians and one lawmaker's statement that migrants who come to Israel from Sudan could become an Al-Qaida cell.

The IDF does think there is "potential" for illegal migrants to serve as a "basis for terror" activities, according to the Southern Command officer. "The presence of a weak population whose allegiance to a country is solely economic is a convenient petri dish for terror nests," he said.

But though five migrants have been placed under administrative detention for short periods on suspicion of terror activities, they have all been released because none of the allegations were substantiated, the officer said.

The comments follow multiple claims over the last few years that illegal immigrants constitute serious security risks.

Prime Minister Benjamin Netanyahu, on a visit to the Egyptian border last year, said the border had been breached "by a stream of illegal infiltrators, who penetrated Eilat, Arad, Tel Aviv - a stream that if we do not stop, can become much stronger."

"For this reason and for a second reason, which is terror, criminal activity, which we have also located over time, we have organized to stop this activity," he said.

In August MK Michael Ben Ari (National Union ) told the Knesset Interior and Environment Committee that infiltrators from Sudan were the foundation for Al-Qaida in the Middle East, and that he "would not let such bases be established in Israel, too."

And in 2009 Yaakov Ganot, then the director of the Population, Immigration and Border Authority, told Haaretz: "We know in principle about foreigners who leave their country and live for years in enemy countries, Syria, Lebanon, Iraq and Somalia. We checked and found that some have [a record of] security offenses."