A key suspect in the murder case of television journalist Soumya Viswanathan was on Wednesday sent to six days judicial custody by a court. Additional Chief Metropolitan Magistrate Kiran Bansal said accused Ajay,who was brought in the court with his face muffled,be sent to custody till March 31. In their application,the police said joint custodial interrogation of Ajay along with Ravi Kapoor,Amit Kumar Shukla and Baljeet Malik,who are in judicial custody till March 28 in BPO executive Jigisha Ghosh murder case,was needed to unravel the murder cases. The three other accused are yet to be formally arrested in the Soumya murder case,which is being probe by Vasant Kunj police station officers. Joint interrogation (of all the four) is required to find out the missing link in this case. So,for the time being,the present accused (Ajay) be sent to judicial custody for six days, the police said.