A man armed with a Kalashnikov-style rifle attacked the Azerbaijan Embassy in Iran's capital Friday, killing the head of security at the diplomatic post and wounding two guards, authorities said. No one immediately offered a motive for the attack in Tehran. Video purportedly taken at the scene showed a lifeless body just inside of the embassy past a metal detector, The Associated Press said. Iranian state media did not immediately acknowledge the attack. A statement from Azerbaijan's Foreign Ministry said that “an investigation is currently underway into this treacherous attack.” It also described the attacker as destroying a guard post with assault rifle fire. Azerbaijan borders Iran to its northwest. There have been tensions between the two countries as Azerbaijan and Armenia have fought over the Nagorno-Karabakh region. Iran in October launched a military exercise near the Azerbaijan border, flexing its martial might amid the nationwide protests rocking the Islamic Republic. Azerbaijan also maintains close ties to Israel, which Tehran views as one of its top regional enemies.