False alarms like this one have become commonplace the world over. But they do nothing to help the government's reputation for caginess as far as alleged terror threats are concerned. Since the 1990’s, the Uighur homeland of Xinjiang has been shaken by sporadic bombings, arson, attacks on officials, and shootouts between Chinese security forces and Uighur militants. There is evidence of Uighur guerrillas have been in cahoots with an alphabet soup of foreign-based Islamic and Uighur groups, Osama Bin Laden and al Qaeda among them.

      But all along, security analysts and Uighur exiles contend, China’s been padding a very thin case of organized militancy, and using it to justify heavy-duty security and religious clamps on the Uighur population. Sure, the Communist Party doesn’t catch nearly the same amount of flak internationally for its policies in Xinjiang that it does for its campaign in Tibetan regions. That’s largely because the U.S. and its allies have been bogged down in their own shadowy, assymetric battles against Islamic elements at home and abroad – and to some extent have backed Beijing’s.

    Still, China has a nervous habit of sending out smoke signals of foul play without delivering much proof.  The pre-Olympic rumblings in Xinjiang have cast this P.R. problem in stark relief. In the absence of verifiable accounts of raids, confessions or arrests, the most compelling proof of the threat China faces has come in the backhanded form of its countermeasures.

    Analysts took note last month, for example, when a Chinese court charged that Uighur separatists from one blacklisted terrorist group had trained in camps on Pakistani soil, the first time China has so implicated its “all-weather” ally. One week later,  neighboring countries announced Pakistan would buy Chinese military aid to combat terrorist activity.

    The most visible move, for anyone living here, came in mid-March. Aviation authorities outlawed air travelers from carrying most any liquids or aerosols onto domestic flights, and ordered airports to tighten searches of passengers and bags. The new regulations came just a few days after word emerged that an air crew had busted Muslim Uighur passengers fixing to set an airplane ablaze.

     Xinjiang's top two honchos unveiled news of the March 7 ploy two days later, at the annual National People's Congress in Beijing. They offered few details, but made the sweeping accusation that one alleged Uighur terrorist group, the East Turkestan Islamic Movement, was scheming against the Olympics. Official media took a traditionally cautious approach, soft-peddling the news at face value.

    Over the next couple days, The New York Times and others leaked online accounts of passengers (The Opposite End of China blogger provides a spirited roundup). In turn, Communist Party media amplified slightly. The accused Uighurs had diddled security, the Global Times reported, by emptying several soda cans and using syringes to refill them with petrol, diluting the nauseous scent with perfume. On March 7, it asserted, a 19-year old Uighur woman sneaked the cans aboard a China Southern Airlines flight from Urumqi to Beijing. She headed to the lavatory in the back of the craft, intending to set the contents of the cans aflame. But one of the stewardesses picked up the scent. The Uighur teen was subdued along with a man suspected of being her accomplice, and the plane made an emergency landing in Lanzhou.

    According to what China Southern boss Liu Shaoyong told Phoenix TV a couple days later, the flight attendant found the container of flammable liquid in the trash receptacle of the bathroom. He did not explain why the Uighur girl might have left it there, whether intentionally or not (a riddle that the Telegraph's Richard Spencer soon took up on his blog).

    But how well-conceived could this botched ploy have been? Details trickled out piecemeal, and skepticism soon arose over how the news was first handled. Why did top Xinjiang apparatchiks who first revealed the averted "air disaster" give such vague accounts? Why did Xinhua pull its initial English-language story? Why did the plane continue on after stopping in Lanzhou? In the early going, there was an independent probe by a respected Chinese newspaper, Guangzhou-based Southern Weekend. But it appears that propaganda authorities put the kibosh on the story before the presses rolled.

    The Southern Weekend report slipped out online anyway. It was promptly translated by Roland Soong, the acclaimed Hong Kong-based blogger at EastSouthWestNorth, who keeps a very reliable bead on newsrooms in Guangzhou. In the report, the Southern Weekend reporter recounted pursuing a passenger over the Internet, who gave him the following account by phone:

    "After flying for about an hour, a passenger remarked that there was the smell of gasoline. The attendant also smelled it because it was too strong.

    "We were flying on a Boeing 757 that day. The plane was not big, and the rest rooms were located between the first-class cabin and the economy cabin. There were more than 200 passengers. The airplane was not full, because there were two vacant rows of seats in the rear.

    "I was seated towards the back, and I heard a quarrel. An Uyghur woman about 20 years old was on her feet. This Uyghur woman was seated towards the front to my right. She was probably in the fourth or fifth row of the economy-class cabin.

    "A man went over there. My guess was that he was the security guard. He held the woman down and found a bottle. He removed the bottle and then escorted her to the restroom. We had no idea what was happening. There was no announcement. During the entire process, there was no chaos. It was very calm. At least I felt very calm. Someone in the rear slept through the whole thing without being aware at all.

    "After noon, we began to feel that the airplane was descending. An announcement came that there was an emergency situation and the airplane was going to land at Zhongchuan Airport in the city of Lanzhou. A few minutes after that announcement, the airplane touched ground."

    Incidentally, his suppressed account tracked with the second-hand version I’d heard that same week. At a dinner, by chance, I met a Han Chinese woman living in Urumqi. She had taken the identical flight to Beijing one day later, on March 8. When it was delayed from taking off without explanation, she rang a friend working as an airport official to ask what was up. Thus she was informed about the incident one day before Xinjiang bosses spoke out about it.

    The Uighur teen, by her account, was an amateur. The young woman made her way to the W.C. clutching the soda cans in full view, which looked sketchy. "Who takes soda cans to the washroom?" Her accomplices were two Uighur men who started an argument in order to divert attention.

    March 7 happened to be the eleventh anniversary of the bombing of a bus traveling past the leadership compound in Beijing, which was blamed on Uighur separatists. Did this source think the "terrorist" plot on the plane was as serious as the government said? "You have to understand China," she replied. “Before the Olympics, there’s no way the government would admit to this if it didn’t happen.”

    The gravity of the matter was manifested most clearly in the new airport security ground rules. In April, officials followed up by prohibiting lighters and matches on planes and cracking down on liquids in express mail cargo as well. The initial ban was promulgated on March 13. There was just two days’ advance notice before it went into effect.

    The haste showed. Lack of notice triggered scenes of chaos at airport security lines -- exacerbated by the fact that Tibetan rioting and protests had broken out that same weekend, propelling many foreign correspondents to Beijing's airport in a breathless rush.  I wound up having two encounters with the new rules -- war against terror, Chinese-style -- in a short span of time. That's a blog for a later time.