The police today claimed to have unearthed a nexus between Punjab-based and foreign drug suppliers with the arrest of four persons, including an African couple, and recovered 4 kg heroin, worth Rs 16 crore in the international market, from them.“The group’s kingpin, Micheal Chinedu Chukwudi, a Nigerian, his wife Catherine Leonard Mrope, from Tanzania, and drug suppliers, Surender Singh and Balwinder Singh, both from Kapurthala, were arrested on Saturday,” said Sajiv Kumar Yadav, DCP (Special Cell).Balwinder and Surender received 3 kg heroin from Micheal and were going to supply it near a petrol pump close to Rohini Jail in Delhi when they were nabbed, the officer said. During interrogation, the duo admitted that they used to supply heroin to various persons in Punjab and Delhi-NCR.Micheal, who lived at Pochanpur in Dwarka (Delhi), had rented two to three apartments there and a house in Gurgaon, where he used to keep heroin, Yadav said. Simultaneous raids were conducted in Dwarka and Gurgaon and the kingpin of the cartel was arrested, and 1 kg heroin was recovered from him, the officer said.In another raid, his wife was also arrested on the charges of illegally staying in the country for nearly two years, forgery and possessing a fake passport, he said.Apart from their Nigerian and Tanzanian passports, counterfeit South African passports with fake stickers of the Indian visa and immigration stamps were recovered from the couple, Yadav said.Micheal said his friends had contacts in Pakistan and Afghanistan, and they used to send heroin to him through human couriers as well as courier deliveries. He was supplying heroin to drug suppliers in Punjab through Balwinder and Surender for the past six months, the DCP said