The Congress in Manipur on Wednesday demanded a CBI probe into the case related to Chief Minister N Biren Singh allegedly pressurising a lady police officer to release an arrested drug kingpin and also sought his resignation on moral grounds.

At a press conference held here, President of Manipur Pradesh Congress Committee (MPCC) M Okendro Singh and Okram Ibobi Singh, leader of Congress Legislature Party (CLP), demanded that the case be handed over to the central investigating agency.

MPCC president said, it is a very serious matter that the chief minister has pressurised the lady police officer to withdraw the case against drug lord Lukhosei Zou from whom a large amount of heroine and "world is yours" tablets were seized as revealed by the police officer.

Ibobi Singh said the case should not be handled by the Manipur Police who were trying to withdraw it.

"It should be handed over to an independent agency like the CBI to find out the facts of the case. For that matter the state cabinet should take a decision that the case of Lhukhosei Zou be handed over to the CBI," Ibobi Singh said.

"If the state cabinet can not take the decision, the chief minister should resign on moral grounds immediately," he added.

Meanwhile, the chief minister has denied the allegations against him.

Talking to the media on the sidelines of a function, Biren Singh said his government would not spare anybody found indulging in drugs and narcotics trade.

Thounaojam Brinda, Manipur Police Service (MPS) officer and former Additional Superintendent of Police, Narcotic and Affairs of Border (NAB) in her affidavit submitted before the Manipur High Court on Monday alleged that the chief minister had pressurised her to release Zhou, a former Chairman of Autonomous District Council (ADC), Chandel district of Manipur.

She had submitted her affidavit in connection with a suo motu criminal contempt case registered by the High Court against her and others following comments on a Facebook post by the officer in which she allegedly undermined and criticised the court for granting three weeks bail to the accused drug kingpin in a 2018 drugs smuggling case.

In the affidavit, she said after an operation commanded by her, the Manipur Police arrested Zou on June 19, 2018 along with seven others and seized 4.5 kg of heroine powder, 2,80,200 'world is yours' tablets, Rs 57,18,000 cash, Rs 95,000 old currency notes and several other incriminating articles.

She further stated in the affidavit that a state BJP functionary visited her and said that the Biren Singh was extremely furious over her defiance to release Zou, who is close to the chief minister's wife, and told her to let him go.

Brinda, however, did not relent.