Officials said the Delhi zonal unit of the NCB began trailing the woman, identified as Bolivian national Maria Laura B Zabala (24), after she arrived in Delhi on June 12 from Addis Ababa (Ethiopia) via Bolivia and Brazil.
The NCB team kept a tab on her movements and intercepted two other men yesterday who had come to meet her in Paharganj area where she was staying in a hotel.
The Nigerian duo, Michael Onyebuchi (33) and Michael Azubuike (40), were allegedly receiving the drug consignment from Zabala when they were caught by NCB officers who had laid a trap.
"The men told us that they were asked by a Nigerian man based in Bolivia to pick up the consignment and hand it over to someone later," senior NCB official said.
He added that the estimated value of the cocaine is about Rs 25 crore.
The official said the woman told them she was allegedly supposed to get USD 3,000 (about Rs 1.9 lakh) for doing the courier job.
The two Nigerians were staying in the country using a forged passport and visa, the official claimed, adding the probe against them and in the alleged drug racket is ongoing.
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