article_snippet.sent: Fearing the city was under attack, officials fired at the aircraft but no evidence of damage was ever found, prompting people to speculate the UFOs were from another world.
article_snippet.sent: The US military claimed The US military recovered a secret research balloon that had crashed, but conspiracy theorists say the wreckage of an alien craft was discovered and hidden.
article_snippet.sent: The incident was reported to the Ministry of Defence and sceptics say The incident could be explained by a nearby police tracking helicopter or a Russian rocket re-entering the atmosphere.
article_snippet.sent: But once again, sceptics say the UFO was an experimental military aircraft.
article_snippet.sent: The mysterious flying objects disappeared when fighter jets gave chase, leading some people to say the UFOs were technically-superior alien craft.
article_snippet.sent: However, a British space researcher called Geoffrey Perry claimed that the UFOs were actually pieces of debris thrown out of the Soviet space station, Salyut-7, which burned up in the atmosphere, Stylist reported.
article_snippet.sent: While the incident was tracked by Nato radar and investigated by the country's military, nothing unusual was found and sceptics believe the sightings may have been of ordinary helicopters.