１９９３年３月２５日，浙江省温州市平阳县水头镇６位知名企业家各收到一封署名“双马帮第七先锋队”的恐吓信，向他们各敲诈２０至５０万元不等的人民币。此案的侦破历时３年６个月，其间还因围捕战斗的失误而导致我一民警不幸牺牲，教训极为深刻而惨痛。回顾、剖析此案的曲折侦破过程，进一步揭示和验证了侦查破案的一条重要准则，即只要能够准确确定侦查方向、范围，又能扎实细致地落实侦查措施，开展侦查工作，任何复杂的案件都是能够得以破获的。方向对，工作实，两者缺一不可。这是被实践反复证明了的必须遵循的侦查破案的一条重要准则。 On March 25, 1993, six well-known entrepreneurs in Shuitou Town, Pingyang County, Wenzhou City, Zhejiang Province each received a letter of intimidation signed by the “Vanguard of the Seventh Pioneer Team” to extort from 200,000 to 500,000 yuan RMB. The investigation of this case lasted 3 years and 6 months. During this period, I was unfortunately sacrificed by a civilian police officer for encircling the battle. The lesson was extremely profound and painful. Recalling and analyzing the twists and turns of the case and further revealing and verifying an important criterion for the detection and detection of crimes, that is, as long as it can accurately determine the direction and scope of investigation, implement the investigation measures in a solid and meticulous manner and carry out investigation, any complicated case Is able to get cracked. The direction of the work, both are indispensable. This is an important guideline that must be followed in the investigation and prosecution proved repeatedly by practice.