A large explosion rocked the central Iranian city of Isfahan Monday afternoon, Channel 2 news reported according to Iranian semi-official FARS news.The report did not reveal the cause of the explosion, which was large enough to be heard throughout the city.Isfahan is home to nuclear experimental reactors, and also a uranium enrichment facility for producing nuclear fuel.The explosion occurred two weeks after a massive explosion west of Tehran which killed 17 troops, including an IRGC officer responsible for the development of some of Iran's most advanced weapons.