TEHRAN — Iran said it successfully test-fired short-range missiles during military drills Sunday by the elite Revolutionary Guard, a show of force days after the U.S. warned Tehran over a newly revealed underground nuclear facility it was secretly constructing.

Gen. Hossein Salami, head of the Revolutionary Guard Air Force, said Iran also tested a multiple missile launcher for the first time. The official English-language Press TV showed pictures of at least two missiles being fired simultaneously and said they were from Sunday’s drill in a central Iran desert. In the clip, men could be heard shouting “Allahu Akbar” as the missiles were launched.

“We are going to respond to any military action in a crushing manner and it doesn’t make any difference which country or regime has launched the aggression,” state media quoted Salami as saying. He said the missiles successfully hit their targets.

The powerful Revolutionary Guard defends Iran’s clerical rulers. It has its own ground, naval and air units and its air force controls the country’s missile program.

The tests came two days after the U.S. and its allies disclosed that Iran had been secretly developing a previously unknown underground uranium enrichment facility and warned the country it must open the nuclear site to international inspection or face harsher international sanctions. The drill was planned before that disclosure.

The newly revealed nuclear site in the arid mountains near the holy city of Qom is believed to be inside a heavily guarded, underground facility belonging to the Revolutionary Guard, according to a document sent by President Barack Obama’s administration to lawmakers.

After the strong condemnations from the U.S. and its allies, Iran said Saturday it will allow U.N. nuclear inspectors to examine the site.

Nuclear experts said the details that have emerged about the site and the fact it was being developed secretly are strong indications that Iran’s nuclear program is not only for peaceful purposes, as the country has long maintained.

By U.S. estimates, Iran is one to five years away from having a nuclear weapons capability, although U.S. intelligence also believes that Iranian leaders have not yet made the decision to build a weapon.

Iran also is developing a longer-range ballistic missile that could carry a nuclear warhead, but the administration said last week that it believes that effort has been slowed. That assessment paved the way for Obama’s decision to shelve the Bush administration’s plan for a missile shield in Europe, which was aimed at defending against Iranian ballistic missiles.

Salami said Iran would test medium-range Shahab-1 and Shahab-2 missiles on Sunday night and a longer-range Shahab-3 missiles on Monday, during drills set to last several days.

Salami said Fateh, Tondar and Zelzal missiles were test fired on Sunday, but did not give specifics on range or other details. All are short-range, surface-to-surface missiles.

He told reporters Iran had reduced the missiles and their ranges and enhanced their speed and precision so they could be used in quick, short-range engagements. He also said they are now able to be launched from positions that are not as easy to hit.

He said the Revolutionary Guards’ current missile tests and military drills are indications of Iran’s resolve to defend its national values and part of a strategy of deterrence and containment of missile threats.

Salami claimed Iran has started “running into difficulties storing so many missiles” with its recent progress on its missile program.

Iran has had the solid-fuel Fateh missile, with a range of 120 miles (193 kilometers), for several years. Fateh means conqueror in Farsi and Arabic. It also has the solid-fueled, Chinese-made CSS 8, also called the Tondar 69, according to the Wisconsin Project on Nuclear Arms Control, a private group that seeks to stop the spread of weapons of mass destruction. The Tondar, which means thunder, has a range of about 93 miles (150 kilometers.)

State media said the Revolutionary Guard tested a multiple launcher for the first time, designed for the Zelzal missile. Tehran has previously tested the Zelzal – versions of which have ranges of 130-185 miles (210-300 kilometers) – but only single launch.

In July 2006, Israeli military officials said their jets had destroyed a missile in Lebanon named Zelzal, which they said Hezbollah had received from Iran and could reach Tel Aviv. Zelzal means earthquake.

Iran’s last known missile tests were in May when it fired its longest-range solid-fuel missile, Sajjil-2. Tehran said the two-stage surface-to-surface missile has a range of about 1,200 miles (1,900 kilometers) – capable of striking Israel, U.S. Mideast bases and southeastern Europe.

The revelation of Iran’s secret site has given greater urgency to a key meeting on Thursday in Geneva between Iran and six major powers trying to stop its suspected nuclear weapons program.

The U.S. and its partners plan to tell Tehran at the meeting that it must provide “unfettered access” for the International Atomic Energy Agency, the U.N. nuclear watchdog, within weeks.

The facility is Iran’s second uranium-enrichment site working to produce the fuel to power a nuclear reactor, or potentially the material for a weapon.

A close aide to Supreme Leader Ayatollah Ali Khamenei said Saturday the site will be operational soon and would pose a threat to those who oppose Iran.

“This new facility, God willing, will become operational soon and will blind the eyes of the enemies,” Mohammad Mohammadi Golpayegani told the semiofficial Fars news agency.

Evidence of the clandestine facility was presented Friday by Obama, British Prime Minister Gordon Brown and French President Nicolas Sarkozy at the G-20 economic summit in Pittsburgh. On Saturday, Obama offered Iran “a serious, meaningful dialogue” over its disputed nuclear program, while warning Tehran of grave consequences from a united global front.

Israeli Foreign Minister Avigdor Lieberman said Saturday the revelation was firm proof Iran was seeking nuclear weapons.

Israel considers Iran a strategic threat with its nuclear program, missile development and repeated calls by President Mahmoud Ahmadinejad for Israel’s destruction. It has not ruled out a pre-emptive strike on Iran’s nuclear sites.

In 1981, Israeli warplanes bombed Iraq’s Osirak nuclear reaction and in 2007, Israel bombed a site in Syria that the U.S. said was a nearly finished nuclear reactor built with North Korean help that was configured to produce plutonium – one of the substances used in nuclear warheads.

Israel’s Foreign Ministry had no immediate comment on the missile tests.

Iranian Vice President Ali Akbar Salehi, who heads the country’s nuclear program, said Saturday that U.N. nuclear inspectors could visit the nuclear site. On Sunday, he told Press TV Iran and the IAEA would work out the timing of the inspection.

The small-scale site is meant to house no more than 3,000 centrifuges – much less than the 8,000 machines at Natanz, Iran’s known industrial-scale enrichment facility, but they could still potentially help create bomb-making material.

Experts have estimated that Iran’s current number of centrifuges could enrich enough uranium for a bomb in as little as a year. Washington has been pushing for heavier sanctions if Iran does not agree to end enrichment.