The consignment of heroin was concealed under hundreds of bags of rock salt (File Photo)

The key accused in the alleged smuggling of narcotics worth Rs 2,700 crore from Pakistan, who was lodged in a jail in Amritsar, died Sunday, with Chief Minister Amarinder Singh ordering a magisterial probe into his death.

The accused, Gurpinder Singh, 29, a rock salt importer, was arrested in connection with the biggest ever narcotics haul in which the Customs Department had seized 532 kg of heroin worth Rs 2,700 crore at Attari border in Amritsar, which was smuggled into India from Pakistan in a truck.

Gurpinder Singh was apprehended by the Customs Department on June 30 and since July 2 he was sent to judicial remand.

His mother Kawaljit told reporters in Amritsar Sunday that Gurpinder Singh was falsely implicated in the narcotics case on frivolous grounds.

The chief minister on Sunday ordered a magisterial inquiry into the accused's death.

Amarinder Singh asked Additional District Magistrate (ADM) Himanshu Aggarwal to conduct a detailed probe into the matter, according to an official spokesperson here.

The ADM was asked to ascertain all facts and circumstances of the death of the under-trial.

The magisterial enquiry will be in addition to the postmortem, which will be conducted by a board of doctors, and the judicial proceedings under the CrPC to be conducted by a judicial magistrate.

The spokesperson said the accused was admitted in the Jail Hospital, Central Jail, Amritsar on July 18. The jail medical officer referred him Sunday, due to his serious health condition, to the Guru Nanak Dev Hospital, Amritsar for treatment. However, he was declared brought dead at the GND hospital, he said.

"Amarinder has directed the ADM to undertake a thorough investigation into the matter and identify the lapses that led to the death of under-trial Gurpinder," he said.

"As Gurpinder Singh was a chronic diabetes patient with deteriorating health condition, he was admitted to the Guru Nanak Dev Hospital, Amritsar, for treatment on July 2 and was discharged from the hospital four days later..," he said.

The smuggling racket's alleged mastermind, based in the Kashmir Valley, was arrested earlier.

The consignment of heroin and another 52 kg of suspected mixed narcotics was concealed under hundreds of bags of rock salt inside the truck, which arrived at Attari from Pakistan through the Integrated Check Post (ICP).