The Israel Air Force has beefed up security at the Nevatim Base in the Negev after a series of infiltrations into the base by Palestinians and Beduin. The IAF base in Nevatim is the largest base in the country, took several years to build and was opened for operations last year. The project, which included the expansion of Nevatim and construction of the largest runway in the Middle East, cost an estimated NIS 1.6 billion. With the transfer of the transport squadrons that had been based at Lod to Nevatim, the base in the Negev became the first IAF base to house both fighter jets and transport aircraft. The decision to move the base to the south was initially made in 2002 as part of the IAF's multi-year plan to help settle the Negev, but the base only opened in 2008. IDF sources said that in the past three months there had been at least four known infiltrations into the base. In response, base commander Brig.-Gen. Eden Atias decided to beef up security. The sources said that in one case four Palestinians were found in a part of the base currently under construction. They were detained for questioning and later released.