A total of 993 grams of cocaine has been recovered.
A Ugandan woman was arrested by customs officers at the international airport here on Wednesday for allegedly smuggling cocaine worth Rs 14 crore into the country.
The passenger, who is suspected to be suffering from the Acquired Immunodeficiency Syndrome (AIDS), had ingested 91 specially-designed pellets containing cocaine, sources said.
After noticing her unusual body movements upon arrival on Saturday, the customs officers, out of "sheer facilitation and goodwill", approached the passenger for providing any possible help to her.
"However, the passenger not only refused to accept any help but also showed disinclination to engage in any conversation, while at the same time continuing to exhibit uneasy body movements," a statement issued by the customs department said.
Seeing the unusual behaviour of the passenger, the customs officers maintained a vigil on her, it added.
The passenger crossed the green channel and was headed towards the exit gate of the international arrival hall, when the customs officers intercepted her, the statement said.
"Upon questioning, the passenger finally divulged that she had swallowed 91 capsules of the narcotic substance," it said.
Since it was an impending emergency, the passenger was admitted to the Ram Manohar Lohia (RML) hospital.
"X-ray scanning revealed that the sigmoid colon (ascending, descending) of the passenger was filled with oval pellets. Under expert medical supervision, an ejection procedure was carried out, which yielded the recovery of a total of 91 pellets in batches," the customs department said.
The entire ejection process lasted for several days during which customs staff maintained round-the-clock vigil at the hospital, it said.
A white powdery substance weighing 992 grams was kept concealed in the pellets, the statement said, adding that a diagnostic test revealed the substance to be cocaine.
Officials said the value of the cocaine seized from the passenger is around Rs 14 crore in the international market.
The hospital authorities handed over the passenger, who is in her mid-30s, to customs officials, who put her under arrest.
The sources said the passenger is suspected to be suffering from AIDS, a life-threatening condition.
They said she might have been allured to smuggle the drug in lieu of money to help her with her medical condition.
This is the second big seizure of cocaine at the Indira Gandhi International (IGI) airport this month.
Around 2.8 kg of the narcotic substance were recovered from a Nigerian woman on December 9, who had arrived at Delhi from Lagos via Dubai. The Ugandan national in the latest case had also followed the same arrival route.
Customs officers at the airport have achieved considerable success against the menace of drug smuggling, the statement said.
This was the 24th case of drug seizure at the airport this year and a total of 32 passengers were arrested in connection with these cases. The estimated value of the drugs seized in these cases is more than Rs 845 crore.