officers and 1,600 other policemen... soldiers assigned to anti-drug duty, members of an elite 150-man unit trained as a shock force[,] live in utter isolation... None of the soldiers... is from the Cali area... In less than 30 days, five of the cartel's seven most wanted members have been put behind bars. In thousands of raids on farms, houses, apartments and office buildings, police have found and seized weapons, drugs, money and—most importantly—business documents, accounts books and lists of payments essential to unraveling the drug lords' multi-billion dollar property and investment empire and their systematic bribes to politicians and other official protectors. 'We use a hammer-and-anvil tactic,' said Colonel Argemiro Serna, commander of the Cali police, in a recent interview. 'The search force raids suspected drug houses and possible hideouts, to try to flush them into movement. Then I send out units on roadblocks and aggressive random searches to trap them.' His boss, National Police Director Ross Serrano, described a more complex overall strategy—first closing down the private security agencies, taxi fleets and beeper companies that gave the cartel leaders bodyguards, safe transport and communications; arresting many of their messengers and lower-level employees to isolate them; and freezing their bank accounts to crimp cash flow. However, with drug use in Europe on the rise, new markets opening up in Eastern Europe and Asia, and the United States reporting a 25% increase in cocaine-related medical emergencies since 1991, the continuing demand for drugs meant that drug trafficking would continue. Samper stated that further measures to be taken should focus on increased international cooperation, including sharing information to speed up investigations and prosecutions, working toward implementing a treaty to stop cartel money laundering through established financial institutions, restricting the trade in precursor chemicals, enhancing international financial support for crop substitution, and holding a world summit on drugs. Foreign relations Shortly after Samper's election and disturbed by the release of the taped phone conversations compromising the integrity of the president-elect, the US Senate unanimously approved a measure that would make anti-narcotic financial aid to Colombia conditional on the government's commitment to fighting drug trafficking. In reply, Colombian foreign minister Noemí Sanín said that Colombia was prepared to fight the drug war without the United States, and that the measure was "disrespectful". On 1 March 1996, after an annual review of narcotics programs in 140 countries, U.S. President Clinton cut off most of his