DUBAI (Reuters) - Iran successfully tested a domestically made anti-aircraft system, its English-language Press TV said on Monday, the latest in a series of military exercises Tehran has trumpeted in the face of hints that its nuclear sites could be attacked. "The mid-range system ... is capable of intercepting targets at a range of 50 km (30 miles) and can fly at an altitude of 75,000 feet," state-run Press TV's website said. An Iranian Revolutionary Guards commander, Brigadier General Amir Ali Hajizadeh, said at a military parade displaying the weapons on Friday: "The system has been manufactured with the aim of confronting (hostile) U.S. aircraft." "The Ra'd air defense system is the first completely indigenous system of the Sepah (Revolutionary Guards), which has been designed and manufactured by committed Iranian technicians in the struggle for self-sufficiency," Hajizadeh was quoted as saying by the Mehr news agency. Hajizadeh, head of the Revolutionary Guards' aerospace arm, was quoted on Sunday as saying Iran might launch a pre-emptive strike on Israel if it was sure the Jewish state was about to attack. Prime Minister Benjamin Netanyahu has made increasing suggestions that Israel could bomb Iran's nuclear sites and has criticized U.S. President Barack Obama's stance that sanctions and diplomacy should be given more time to stop what Israeli and U.S. officials see as an Iranian bid to develop a nuclear bomb. This has raised speculation about possible Israeli military action ahead of U.S. elections in November. Washington has not ruled out last-resort military action if no deal can be reached on curbing Iran's nuclear programme. Iran denies seeking nuclear weapons capability, saying its atomic activity is peaceful, aimed at generating electricity. Tehran launched a submarine and a destroyer into the Gulf from the port of Bandar Abbas last Tuesday at the same time as U.S. and allied navies were conducting exercises in the same waters to practice keeping oil shipping lanes open. In a separate report on Monday, Ali Fadavi, a naval commander in the Revolutionary Guard Corps, said Iran had simultaneously test-fired four sea missiles in the Gulf on Sunday. During exercises, four sea missiles were simultaneously fired at a big sea target yesterday. The (targeted) vessel sank in about 50 seconds," Fadavi said, according to the semi-official Fars news agency. Iran has said it could hit Israel and U.S. bases in the region if it comes under attack. It has also threatened to block the Strait of Hormuz, the neck of the Gulf through which 40 percent of the world's sea-borne oil exports pass. Writing by Zahra Hosseinian; Editing by Mark Heinrich