Jalandhar, July 22 -- The police remand of inspector Gurinderjit Singh Nagra, who is behind bars in connection with a corruption and extortion case involving a US-based family, has been extended by one more day, police said on Tuesday. Nagra, who was arrested on Saturday, was produced in a court in Hoshiarpur's Dasuya after his three-day police custody ended on Tuesday. He was recently indicted by the Federal Bureau of Investigation (FBI) as part of 'Operation Hard Ball' for allegedly trying to extort $400,000 (Rs.3.81 crore) from a family based in Los Angeles by threatening to implicate their relatives in Punjab in a murder case. "The investigation is still on as Nagra, so far, is found have received illegal gratification of Rs.16 lakh in the case," said Vineet Ahlawat, Jalandhar rural superintendent of police (investigation), who has been investigating the case. He added that further disclosures, if any, will be made later by senior officials. Jalandhar range DIG Naveen Singla had ordered a probe against the suspended Tanda SHO, Nagra, last week. He was initially shifted to the police lines in Hoshiarpur and Ahlawat was directed to investigate the matter. Following his arrest, Nagra was formally named as an accused under Section 308 (extortion) of the Bharatiya Nyaya Sanhita and relevant sections of the Prevention of Corruption Act in the FIR registered at the Tanda police station on January 16 in connection with the murder of Balwinder Singh in Miani village by three unidentified motorcycle-borne assailants on January 15....