On the anniversary of the September 11, 2001 attacks on Washington D.C. and the Twin Towers in New York, the Israeli military has announced that al-Qaeda recently tried to hijack a Saudi F-15E fighter and crash it into a major office tower in Israel.
Because of this, Israel is trying to get the U.S. to convince the Saudis to remove their fleet of 50 F-15Es from the King Faisal Air Base in nearby Tabuk. They were flown there in March, 2003 and Saudi Arabia has refused to return them to their bases in other parts of the country. This gives rise to the speculation that they may be planning to cooperate with al-Qaeda on a strike against Israel. The planes were sold to the Saudis by the U.S.