They said the suspended officer was produced in the special NIA court along with the two terrorists, who he was helping travel out of Jammu and Kashmir, and their two associates.
Syed Irfan, brother of a Hizbul Mujahideen terrorist arrested along with Singh, was also produced in the court by the NIA after it arrested him on Thursday.
The NIA sought 15-day custody to interrogate the five, officials said, adding the court granted the request.
The accused were brought to the court in bullet-proof vehicles with their faces covered.
A battery of mediapersons was seen outside the court complex.
The NIA, which took over the investigations into the case last weekend, brought them here on Wednesday on a transit remand from Kulgam in south Kashmir.
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