Iranian claims Wednesday that it now has some 5,000 centrifuges up and running underlines the danger posed by the extremist Iranian regime and the need to stop its nuclear march, senior diplomatic officials said in Jerusalem. The comment came when one of the officials was asked to respond to Gholam Reza Aghazadeh, Iran's nuclear chief, who said Iran had more than 5,000 centrifuges operating at its uranium enrichment plant and would continue to install centrifuges and enrich uranium to produce nuclear fuel for the country's future nuclear power plants. Uranium enriched to low level is used to produce nuclear fuel. Further enrichment makes it suitable for use in nuclear weapons. "At this point, more than 5,000 centrifuges are operating in Natanz," said Aghazadeh, who is also the head of the Atomic Energy Organization of Iran. He spoke to reporters during an exhibition of Iranian nuclear achievements at Teheran University. The new number of working centrifuges is a significant increase from the 4,000 Iran said were up and running in August at the plant in the central Iranian city of Natanz. Iran has said it plans to move toward large-scale uranium enrichment that will ultimately involve 54,000 centrifuges. Israeli officials have said in the past that Iranian claims of nuclear technological advances are often exaggerated, to create the impression that its nuclear program is so far down the line that nothing can be done to stop it. Also Wednesday, Iran successfully launched a rocket into space. State television called the rocket the "Kavoshgar 2" (Explorer 2) and reported that it returned to earth 40 minutes after launching on a parachute after performing its functions in the lower reaches of space. Teheran unveiled the first Iranian-made satellite, called Omid (Hope) and inaugurated its first space center earlier in February when it launched a research rocket. Tal Inbar, a Research Fellow & Secretary of the Space Research Center at the Fischer Brothers Institute in Herzliya, said that the research rocket was launched from a launcher that resembled the type used to launch the Zelzal missile that Iran supplied Hizbullah before the Second Lebanon War. Inbar said that the rocket worked on solid fuel and was a two-stage research rocket that could "scratch" the outskirts of space, but was not capable of carrying a satellite. AP contributed to this report.