China's transnational criminal underworld has been served a strong warning with the arrests of four 'untouchables' and the dismantling of one of the world's biggest drug smuggling rings, a senior US agent said yesterday. The latest intelligence showed the business of a number of international drug traffickers had suffered heavily as a result of raids by the first joint Sino-US drug taskforce on May 16, the Beijing-based officer said. He said simultaneous raids in Fujian, Yunnan, Guangdong and Hong Kong aimed at the highly organised crime ring known as the 125 group had sent shockwaves through the underworld, both in China and overseas. Crime bosses who previously thought themselves beyond the reach of international law were now scaling back smuggling operations in the region, he said. The raids resulted in the indictment of 25 people by Manhattan federal court. They are accused of smuggling more than 680kg of heroin out of the Golden Triangle, through China into the US since 2000. Among those arrested was the group's alleged leader, Wong Kin-cheung, also known as the Fatman. Wong, 56, a Hong Kong citizen, and his three partners, referred to as 'the untouchables' because mainland authorities believed they would never be caught, are in detention awaiting trial on drug trafficking charges in Fuzhou. Under mainland law, they face the death penalty. Three Hong Kong-based members of the 125 group were also arrested and are facing extradition to the US on charges of conspiring to commit an offence relating to dangerous drugs. Mak Kam-fai, 43, Tsui Yan-ko, 48, and Too Ka-keung, 35, are due to face committal proceedings on July 14. 'It sends out a very strong message. A very powerful warning,' said the agent. 'We were very fortunate in that we were able to pick up all the major players very quickly.' Agents in Canada, India and the US also led simultaneous drug raids. The agent said it was the first time Chinese drug lords had been found to be operating in India. 'The case has resulted in the removal of a major threat. But it has also exposed how Chinese drug traffickers are looking to shift their operations away from the stringent law detection in this region and into the less traditional drug producing areas,' he said. 'It shows [drug traffickers] are branching out, taking opportunities, and this is something we must be aware of.'