A shimmering blue and white object hovered past the cockpit window of the Xiamen Airlines plane as it started its decent into Nanjing. It drifted across the path of the passenger jet, the pilot later told officials, then accelerated sharply and disappeared at lightning speed into a bank of cloud. His story might have been dismissed as a delusion had it not been for the fact that two other pilots in different planes hundreds of kilometres apart independently radioed similar reports to air-traffic controllers within minutes of each other. One was flying a Shandong Airlines plane 120 kilometres north, also over Jiangsu Province. The second was flying 300 kilometres south over Tonglu, Zhejiang Province. All three pilots flying on that November morning last year described the UFO as a blue and white oval-shaped spacecraft that moved noiselessly across the sky then sped away at a velocity sufficient to render it visible, within a brief period, from three aircraft hundreds of kilometres apart. There are more UFO sightings over China than anywhere else in the world, with one in every five 'flying saucers' reportedly seen over the mainland. It has the world's biggest network of clubs, the China UFO Research Organisation, and a monthly UFO magazine that sells 400,000 copies. It has some of the most spectacular sightings and some of the most bizarre tales of encounters; estimates by the UFO Research Organisation suggest more than half of China's 1.2 billion population believes in flying saucers. Sightings are reported widely by state media and pilots talk openly about close encounters, without the fear their counterparts have in the West of being dismissed as dangerous cranks. In 1998, a Chinese jet fighter reportedly played a game of cat and mouse with a UFO picked up by four radar stations as it flew over a military training base near Changzhou. More than 100 people watched from the ground as the two-seat Jianjiao armed interceptor chased the UFO, which was described as a mushroom-shaped dome with rotating bright lights underneath it. The pilot said it looked 'like the UFOs in foreign sci-fi movies'. With the air force jet about 4,000 metres away, the UFO shot upwards, leaving it trailing in its wake. A request from the pilot to fire on the UFO was refused by ground control, official media reported. Wendelle Stevens, an 80-year-old former US fighter pilot and one of the world's top UFO investigators, says the emergence of China as the epicentre of UFO activity is all the more remarkable considering there were no officially recorded sightings until less than 25 years ago. 'UFOs seem to be taking a very close interest in China,' Stevens said from his home in Tucson, Arizona. 'From 1949 until 1979 the bamboo curtain was in place and no information about what was happening was coming in or out - but that's all changed now.' Even though UFOs were reportedly sighted across China as long ago as the Sino-Japanese War in the 1930s and 40s, there was an official reluctance in the post-war years to recognise the phenomenon because of a widely held belief that they were American spy planes, according to Stevens. The Russians convinced the Chinese government that UFOs were a United States trick,' he says. 'They persuaded the Chinese to give them all the information they had. During those years the only cases anyone heard about were the spectacular ones.' That changed one day in 1979 when two dish-shaped objects reportedly flew backwards and forwards over Beijing at a height of about 150 metres. There were thousands of witnesses, and the first official reports of flying saucers in China's state media meant the newspapers were full of the incident the following day. Stevens, co-author of UFOs Over Modern China, which documents 400 sightings, said: 'When those newspaper stories appeared, people who had had experiences thought the lid was off so they began writing letters to newspapers describing what they had seen - thousands and thousands of letters.' A group of scientists at Wuhan University, led by former diplomat Professor Sun Shili, was given permission to start researching the phenomenon. A network of UFO enthusiasts' clubs was formed under the umbrella of the Chinese UFO Research Organisation. Stevens recalls his first meeting with Sun, in Mexico City in the early 1980s. 'My opening words were, 'Do the Chinese have crashed UFOs in their possession?' He answered: 'Of course.' Although Sun did not elaborate on the whereabouts of these aircraft, he said China was taking a different approach to the US with its research. 'Sun said the Chinese were researching crashed UFOs to produce airliners that could rise and descend vertically, and unlocking the secret of unlimited supplies of energy. The US was using the technology from crashed UFOs to build bigger and better weapons. 'The Chinese are quite far along in that field [aeronautics]. They have experimental vehicles that rise and descend vertically. They haven't got them in production but when they do - and it might take 10 years - the economic balance of the world could shift. They are going into space using the knowledge they have got from the examination of crashed vehicles,' Stevens says. Sun, meanwhile, revels in academic freedom: an estimated 30 per cent of the Research Organisation's core members are Communist Party officials. Most are engineers and scientists, and members must have a degree and have published research before they can be admitted to its inner sanctum. The group receives government funding, its research papers are covered by state media and military officials attend its meetings. As long as it steers clear of politics, respect is assured. Now 66 and retired, Sun worked in the diplomatic service and was once a translator for Mao Zedong. His only encounter with a UFO came in 1971 when he was working in a rice paddy after being sent to a labour camp in Jiangxi Province during the Cultural Revolution. 'I thought it was a Soviet spy plane,' he says. It was only years later when he read Western books on the subject that he realised it might have been a flying saucer. Sun is on record as saying he has a 'gut feeling' that there are 'aliens living among us, masquerading as humans'. One is reminded of the film Men In Black. Moon Fong has an air of disappointment that hovers over her like a UFO that won't go home. She is 43, single, lives with her mother in Sha Tin, and eight years after seeing her only spaceship still hasn't been abducted by aliens. 'I want to go up in a flying saucer,' she says wistfully over lunch. 'I want to go up and see an alien planet - badly. I wish I was a contactee - I really wish I was.' Moon (not her real name) set up the Hong Kong UFO Club after seeing a UFO in Mexico. At the time she was staying with a cult-like group led by a mystic and didn't regard her experience as unusual, she says. 'Everyone around me had seen a UFO, been to another planet, been abducted by an alien. It was only when I came back to Hong Kong that I began to think maybe the encounter was meant for me to bring the message back.' In the early days it was a mission. 'I was energy-high. Whenever I met UFO people it was like an instant merging, an instant hugging.' Now she feels that energy and sense of mission are ebbing and says she thinks 'they' - the aliens - want her to slow down, sort out her life and play more of a background role in the UFO movement. She clearly isn't about to be whisked off her feet to another planet, however much she'd like to be. The Hong Kong UFO Club has more than 300 members, including academics, company executives and a number of well-known movie industry figures. Moon says 'at least 100' have seen UFOs or dreamed about them 'in an abnormal way or frequently'. She claims 'dozens' have been awake during their extraterrestrial encounters. Despite its proximity to the mainland, Hong Kong is not the best place to be if you want to be abducted by an alien, it seems. 'They don't stop,' Moon says. 'They pass over, flying north to south and south to north. It looks like they are going back and forth to China from the ocean. No one has seen any landing. A lot of people have seen them from the Wah Fu Estate, southern Hong Kong Island, and over Tolo Harbour, skimming across the sky. 'It's too crowded and polluted in Hong Kong for UFOs to land. China on the other hand is a big place. Often they show up where there is military activity. That's why the Roswell incident [the alleged UFO crash of 1947 in New Mexico, after which the US government supposedly captured aliens] happened, and why there are so many sightings in Mongolia, where there are a lot of military installations from the Cold War era.' The Roswell incident has an eerie parallel in China in the reported discovery of alien skeletons in the remote mountains of Bayan-Kara-Ula, Qinghai Province, in 1937. Archaeologists apparently found a group of skeletons with abnormally large heads and small bodies in a cave tomb. The skeletons were reportedly surrounded by granite discs with strange hieroglyphics that, according to one translation, tell of a UFO crash 12,000 years ago. The Hong Kong club has contacts with mainland UFO groups but Moon gives the impression the relationship isn't an easy one. 'A lot of them are weird,' she says. 'We are suspicious about whether some of them are sane. They all want to have contact with us because we are the ones with the money and power to get things done. A lot of them want to live here. When you ask them for photographs they ask you for money. They want money for anything they can offer you because they are so poor.' Moon acknowledges, however, that mainland UFO clubs operate in difficult political circumstances. 'They can't do anything that is not scientific otherwise they will be treated like the Falun Gong. If they did anything seen as remotely religious or political they'd be banned.' What if all the stories are true? What if flying saucers really are shooting over Hong Kong and China? And why? Why don't they come down in peace or invade us and demand to be taken to our leaders? It is a question Stevens has spent much of the past half century pondering and one for which he has a plausible answer. 'It appears to me they are simply observing and reporting back to their own societies,' he says. 'They are far ahead of us technologically. They have no need of anything here. They are simply observing us at a stage when we are birds about to leave the nest. They have already left the nest and live in space in huge planetoids and have produced a utopian society. There are thousands of mother ships big enough to hold half a million people and travel forever. They are watching us approach the stage where we try our first flight.' Sun believes China is seeing a surge in UFO activity now for the same reason the US was attracted it in the 1950s: it is emerging as the world's leading power and extraterrestrials are almost as interested in China as foreign investors appear to be. 'In the past, there were more flying saucers over developed countries like the US,' he says. 'Now China is developing, and this is what has aroused the interest of beings from other worlds.' Moon believes the aliens have a more esoteric motive and are trying to show at least some of us the way to a better life. 'People who have seen UFOs say everything is so warm, so heavenly. It is like an inner knowing that there is something better. There are much better worlds everywhere. This is really negative, this world. It's just that most people are very good at pretending.' There is a faraway look in her eyes as she declares: 'There is something better out there. I know there is.'