Khan and BSF head constable Abdul Rasheed were arrested last week in connection with an espionage racket being run by Pakistan's external spy agency ISI, which used to pay them in return for confidential information.
An official privy to the investigation said Khan's response during his interrogation raised suspicion about the jawans having shared "secret" documents with the ISI operative.
"A team from the inter-state cell of crime branch, led by an inspector rank officer, will be sent to Rajouri tomorrow to investigate the matter," said Joint Commissioner of Police (Crime) Ravindra Yadav, adding that the Army personnel will face arrest if they are found involved in the espionage racket.
Meanwhile, sources said the police are yet to identify the alleged source in the Pakistani High Commission in Delhi of the ISI handler, who was directly in touch with Khan and Rasheed.
Khan claimed he was told by an ISI man based in Pakistan that the source at the High Commission would help him secure a visa with which he could visit that country for availing more resources.
Investigation has revealed that Rasheed had double-crossed Khan and established direct contact with a Pakistani handler who earlier used to assign tasks to the duo through the latter, who was put on a permanent payroll, receiving around Rs 20,000 per month through official banking channels, said a police source.
Khan was arrested from the New Delhi Railway station while he was on his way to Bhopal on Thursday. He was taken to his native place Rajouri from where the police arrested Rasheed.
The police recovered several secret documents related to troop positions and movements from their possession. Both accused have been booked under relevant sections of Official Secrets Act.
