Iran has dug mass graves in which to bury U.S. troops in case of any American attack on the country, a former commander of the elite Revolutionary Guard said.

The digging of the graves appears to be a show of bravado after the chairman of the U.S. Joint Chiefs of Staff, Adm. Mike Mullen, said last week that the U.S. military has a contingency plan to attack Iran, although he thinks a military strike is probably a bad idea.

The U.S. and some of its allies accuse Iran of using its civilian nuclear program as a cover to build nuclear weapons. Iran has denied the charges, saying its nuclear program is geared merely toward generating electricity, not bomb.

Gen. Hossein Kan'ani Moghadam, who was the Guard's deputy commander during the 1980s, said graves have been dug in Iran's southwestern Khuzestan province, where Iran buried Iraqi soldiers killed during the ruinous 1980-88 war between the Islamic republic and Iraqi leader Saddam Hussein's regime.

"The mass graves that used to be for burying Saddam's soldiers have now been prepared again for U.S. soldiers, and this is the reason for digging this big number of graves," Moghadam told The Associated Press Television News late Monday. He did not say how many were prepared.

Footage obtained by APTN showed a large number of empty, freshly dug graves in a desert region of Khuzestan. The digging of the graves was first reported earlier this week by Iran's semiofficial news agency Fars.

Moghadam repeated warnings that Iran will retaliate against U.S. bases in the Gulf if there is an attack on Iran. The U.S. Navy's 5th Fleet headquarters is based just across the Gulf from Iran in Bahrain.

If U.S. forces attack, "Iran will have no choice but to strike the American bases in the region," he said. "The heavy costs of such a war will not be just on the Islamic Republic of Iran. America and other countries should accept that this would be the start of an extensive war in the region."

The war of words has intensified between Iran and the United States after the U.N. Security Council imposed a fourth round of tougher sanctions in June in response to Iran's refusal to halt uranium enrichment, a technology that can be used to produce nuclear fuel or material for an atomic bomb.

The U.S. and Israel have said military force could be used if diplomacy fails to stop what they suspect is an Iranian nuclear weapons program.

(This version corrects that Moghadam is a former Guard commander, not a current one, and spoke to APTN, instead of Fars.)

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