A senior Iranian military official said on Saturday that the U.S. government should speedily apologize to Tehran for what he called \"illegally violating Iran\'s airspace,\" the official IRNA news agency reported. Brigadier General Masoud Jazayeri, head of the cultural and propaganda branch of Iran\'s Joint Chief of Staff, was quoted as saying by the IRNA that Iran\'s defensive measures would certainly not be limited to its geographical boundaries in case of facing any aggression. Iranian media reported on Sunday that the Iranian military had downed a RQ-170 U.S. reconnaissance drone aircraft in the eastern part of the country after finding it had transgressed the eastern border. Jazayeri called the violation of Iran\'s airspace \"unacceptable behavior,\" the IRNA report said. As Iranian state TV showed on Thursday the footage of the U.S. drone shot down by Iranian troops in the eastern region, Iran has also urged the United Nations to condemn the violation of its air space by the U.S. drone, and said Tehran would seek \"clear and effective measures\" to end such \"dangerous and unlawful acts\" against the country.