Special Judge Munish Markan extended Singh's custody after the Delhi Police said that he was required to be further confronted with three other accused persons -- Javed Iqbal, Syed Naveed Mushtaq and Imran Shafi Mir -- arrested in the case to unearth their respective roles.
The court also extended the custody of Iqbal, Mushtaq and Mir till April 10 on a plea by the police.
The Delhi Police said that the accused were required to be interrogated further to identify the other persons involved.
"The custody was required to ascertain the identity of other handlers," the police told the court.
The police said that further interrogation was required to unearth the larger conspiracy and role of the accused, to trace the details of financial transactions, verify and trace other offenders.
Defence advocate Prashant Prakash opposed remand on the ground that there were no fresh and adequate reasons for the remand demanded.
He further said that the grounds of remand were the same as the previous ones, hence police could not be allowed to interrogate the accused further.
The court directed the police to conduct Singh's medical examination after every 48 hours.
Singh was suspended from the Jammu and Kashmir Police in January this year.
The Delhi Police's Special Cell had brought Singh to the national capital from Hira Nagar Jail in Jammu and Kashmir.
Earlier, the court had sent Syed Naveed Mushtaq and others to police custody till April 3 after police said that he and other co-accused were planning to execute terror attacks in Delhi and other parts of the country and targeted killings of protected persons.
The police said that Mushtaq, the commander of Shopian district of Hizbul Mujahideen, used to chat with other co-accused and militants through various internet platforms, including darknet chat.
"Mushtaq, along with other militants of Hizbul Mujahideen, were planning to execute a terror attack in Delhi and other parts of the country and targeted killings of protected persons," police told the court.
The Delhi Police filed a first information report under Section 120B of Indian Penal Code, and sections of the stringent Unlawful Activities Prevention Act (UAPA).
The FIR said that the youths of Jammu and Kashmir and Punjab were being trained for carrying out terrorist activities. The FIR also mentioned D Company and Chhota Shakeel.
According to the FIR, the Special Cell had received an input that the D Company was funding pro-Khalistan terrorist organisations in Punjab.
Under this FIR, Singh was taken into custody. The Special Cell had also interrogated Singh regarding the Khalistan angle, the police said.
Although Singh was not named in the FIR, the Special Cell had some inputs on the basis of which the enquiry was carried out and the suspended DSP was questioned.
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