It's time for the United States to hold Iran accountable.

Iran removed a powerful missile from a launchpad east of Tehran within the past few days, Fox News has learned, as U.S. and Iranian officials continued trading public barbs about the Islamic Republic's missile tests.

The Pentagon is concerned because Safir missiles use the same components as those needed for an intercontinental ballistic missile. Iran’s ballistic program has “expanded dramatically” in the past 10 years, a senior U.S. defense official told Fox News.

New satellite imagery from Feb. 3, obtained exclusively by Fox News from ImageSat International and verified by U.S. officials, showed Iran preparing a Safir for launch. That missile is the type Iran has previously used to put a satellite into space.

It has been two years since Iran has launched a Safir into space, according to officials. But there has been a flurry of activity on an Iranian launchpad that U.S. officials have been watching closely, since the launch of a ballistic missile from the site last week.

In a surprising about face, Fox News learned Tuesday morning that Iran’s missile had been removed from the launchpad. It was not immediately clear why.

On Jan. 29, Iran launched a new type of medium-range ballistic missile prompting an emergency meeting of the U.N. Security Council on Jan. 31. A day later the White House issued a strongly worded statement from National Security Adviser Mike Flynn putting Iran "on notice." President Trump tweeted a similar statement soon after.

Days later, American intelligence officials watched as Iran quickly cleaned up the site and prepared another missile on the same launchpad near Semnan, about 140 miles east of Tehran, before it was removed.

ImageSat International reported a "missile integrations facility" near the launchpad that is normally quiet had a host of visitors on February 3, when the new missile showed up on the launchpad. Another satellite photo showed an additional Iranian missile launcher and nine vehicles in the desert not far from the launchpad.

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