Egypt\'s public prosecutor on Saturday extended by 15 days the detention of a man suspected of spying for Israel, a judicial source told AFP. Ilan Grapel, a US-Israeli dual national, \"will remain in custody for another 15 days pending investigation,\" the source said. His remand had been due to expire Monday. American-born Ilan Grapel was arrested last month in a Cairo hotel and placed in preventative detention for 15 days. He has been accused of being an agent with Israel\'s Mossad intelligence agency and of sowing sectarian strife and chaos in Egypt after a popular uprising forced president Hosni Mubarak to step down on February 11. Two days after Grapel\'s arrest in Egypt, which in 1979 became the first Arab state to recognise Israel, Israeli Foreign Minister Avigdor Lieberman strongly denied he was spy. \"I can say categorically that this student, who may have behaved bizarrely and irresponsibly, has no ties with Israeli, American or even lunar intelligence services,\" Lieberman told Israeli army radio. \"This is a mistake or bizarre behaviour on the part of the Egyptian authorities, who have received full explanations from us,\" he added.