Acting on a tip-off, Indian customs officials carried out special frisking of some suspected passengers when the train arrived from Pakistan at the Attari railway station on Monday evening.
During the frisking, the officials seized 14 kg of heroin from four Indian passengers, including two women.
The women were identified as Saddiqiquan, a resident of Mazaffarnagar in Uttar Pradesh and Bundila, while their male co-passengers were Akhtar Abbas and Ali Baksh, residents of Bulandshahr. All of them went to Pakistan on January 19.
During interrogation, they said that the consignment was given to them at the Lahore railway station to deliver to a person who would contact them on reaching India.
The four are being questioned about the persons who were to collect the consignment on the Indian side, the custom officials said.
After the November 26 terror attacks in Mumbai, Indian security agencies have enhanced frisking at the Attari railway station and the Attari check post on the land transit route.
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