A veteran SCMP reporter, Kevin examines the good, bad and ugly sides of life in the city. Forty years ago this week, Hong Kong trembled. On the border, for the first time, the British army and elements of the Chinese military were in face-to-face confrontation, weapons drawn, fingers on the triggers. It was the nightmare everyone prayed would never happen. The focal point was the divided border village of Sha Tau Kok, where trouble had been brewing for weeks. It exploded on July 8, 1967. As a mob stormed and stoned a police post in the town, police fired wooden bullets and tear gas. Suddenly, a machine gun opened up. Within minutes five policemen lay dead, another 11 injured. Sniping continued from houses on the Chinese side of the border. Police were pinned down and had difficulty reaching the dead and treating the injured. Under intense pressure and determined to keep the situation from spiralling out of control, the Hong Kong authorities decided reluctantly to play the only card they had left; they called in the army. There were at least 5,000 British soldiers based in the New Territories, including a battalion of Gurkhas close to Sha Tau Kok. The government was hesitant to call on them. In the 18 years since 1949 when the People's Liberation Army occupied the north bank of the Shenzhen River, there had never been a serious incident. Urgent discussions were held between Government House, the commander of British forces and police. The risks were awesome. If the Gurkhas moved on to the border and were attacked, they would have to fire to defend themselves. This could lead to a direct clash with Chinese forces who had just demonstrated their willingness to kill defenders of Hong Kong. If units of the British Army and the PLA started shooting at each other at Sha Tau Kok, would the fighting spread along the border? Could this lead to a major incursion into Hong Kong? Finally, it was agreed the only way to rescue the police pinned down by machine gun and sniper fire was to send in the troops. It was a bold gamble. Silently, the tough Nepalis moved into the village, weaving behind vehicles and buildings to secure tactical positions on rooftops and behind walls. They didn't fire a shot. With their appearance, the last of the riotous mob slowly melted away, including the armed intruders. The period of danger, when the slightest lapse of judgment could have led to a disastrous clash, gradually eased. Tension stayed high for months. The postmortem examinations began. The first incident in the 1967 summer of blood, bombs, gas and deaths took place on May 6, when police arrested 26 protesting workers at the Hong Kong Artificial Flower Works in San Po Kong. That action provoked riots and protests. The localised labour upheavals became entwined with the lunacy of the proletarian revolution that was ripping China apart. Suddenly the streets of Central seemed choked with demonstrators waving The Thoughts of Chairman Mao. By June 10 the usually placid town of Sha Tau Kok, where the border runs down the middle of the main street, was caught up in revolutionary fury. A mob of 800 villagers, many from the Chinese side of the border but including Hong Kong villagers, staged anti-British demonstrations outside the police post. Two weeks later, 500 farmers and shopkeepers waving banners, hurling stones and wielding iron bars, attacked the police post. Among them was a village representative, Law Kwai, 54. (He was later charged, convicted and jailed for five years.) Police fired tear gas to disperse the crowd; some had tried to torch the rural committee building. So when hundreds of angry demonstrators once again surrounded police on July 8, there was an apparent established pattern; they were violent and threatening but could be controlled. Then the machine gun started its chattering death call. The trigger was pulled by local militia. Both London and Beijing issued angry proclamations, but behind the scenes there was relief that the brief but bloody clash had not escalated. Within two days, the militia at Sha Tau Kok was replaced by disciplined regular PLA soldiers. The five police killed that day, three Chinese and two Pakistanis, were among an official death toll of 51 people who lost their lives during the 1967 disturbances. Of these, 15 were killed by bombs. Courts convicted 1,936 people; 465 were jailed for unlawful assembly, 40 for possessing bombs and 33 for offences connected with explosives. Soon after the Sha Tau Kok murders, the British government drew up a secret emergency report on how it could withdraw from Hong Kong if China invaded. This was based largely on fears raised by the possible scenario of the clash at Sha Tau Kok escalating into full-scale fighting along the border.