KANDAHAR, Afghanistan- Iranian military advisers have been training Taliban fighters in Afghanistan on the use of surface-to-air missiles, a potential game changer in the war if insurgents can use such weapons effectively, several current and retired military officials told The Washington Examiner. We know the [Islamic Revolutionary Guard Corps] has been training Taliban fighters in the use of surface-to-air missiles, said a military official in Afghanistan with knowledge of the situation. As of the moment it is uncertain whether the Taliban has access to the weapons systems necessary to utilize this training against the coalition. That is the key question whether the Iranian government or other supporters of the Taliban have so far supplied the weapons necessary to conduct significant attacks against U.S. or coalition aircraft in the region, military sources said. The Iranians reportedly possess Chinese portable surface-to-air missiles of the type that would threaten coalition aircraft. When asked whether Iran was training Taliban to use surface-to-air missiles, supplying weapons or had used surface-to-air missiles against U.S. aircraft recently shot down in Afghanistan, a Pentagon official said the Defense Department cannot address questions this specific and of this nature at an unclassified level. NATO has had an advantage with the use of helicopters and aircraft since the beginning of the war. Insurgents have been armed mainly with small arms, improvised explosive devices (IEDs) and rocket propelled grenades. Since the Soviet invasion, shoulder-fired missiles have circulated among militants, but they have been of limited use, in part because they have damaged parts or dead batteries and in part because the Taliban fighters lacked the training to use them. An Afghan official based in Kabul said that Iran has been training the Taliban in using the weapons and may be supplying them. The official said that an Afghan intelligence report revealed that Iran was supplying batteries for the older model surface-to-air missiles. Such intelligence is worrisome for U.S. and NATO officials. Surface-to air-missiles supplied covertly by the United States to mujahideen fighters in the 1980s played a crucial role in the defeat of Soviet forces in Afghanistan. Coalition forces are even more dependent on moving troops and supplies through the air than the Red Army was, experts said. In July, WikiLeaks released classified internal U.S. military reports describing Taliban insurgents firing on an American Chinook helicopter with a surface-to-air missile. There are 11 references in these reports to insurgents having Chinese HN-5 surface-to-air missiles. Military officials are not confirming these reports. Retired Army Maj. Gen. Paul Vallely said U.S. Defense officials have known for some time that Iran has been training Taliban in IED and surface-to-air missile training. And we do nothing about it, he said.