The seizure was one of the biggest made by Customs in recent times, the official said.
Over 15 kg of heroin worth Rs 100 crore was seized at the airport in Chennai on Friday and two Tanzanian nationals were arrested in this connection, said a top Customs official.
Acting on inputs that some drug was being smuggled into India from Africa, the Customs Department detained a 46-year-old woman and her 45-year-old associate for interrogation, said Customs Commissioner Rajan Chowdhry in a press release.
Since the two were evasive in their replies during interrogation, the sleuths examined the baggage and recovered the drug.
The heroin was concealed in packets and some spicy powder was sprinkled to camouflage the smell emanating from the narcotic, he said.
The seizure was one of the biggest made by Customs in recent times, he said.
It is learnt that the woman took up the journey to India citing medical treatment along with her attendant to a multi-specialty hospital in Bengaluru.
The visa to take up the travel (to India) was granted on the basis of a communication from the hospital, he said.
Since the duo did not get a direct flight to Bengaluru they landed in Chennai and were arrested, he added.