Santhosh Kumar, first accused in the murder of liquor contractor Mithila Mohan, was remanded in police custody for 12 days by the Judicial First Class Magistrate Court here.
Mr. Kumar, arrested from Thrissur by a Crime Branch team on Wednesday, is charged with murder and criminal conspiracy.
V.A. Mohanan was shot to death at his house in Vennala on April 5, 2006.
The police said business rivalry between Mohan and Kumar was the reason for murder.
Kumar allegedly asked Pandiyan, a criminal from Dindigul in Tamil Nadu, to hire two shooters to kill Mohan.
The deceased Pandiyan is second accused in the case. Madivanan and Uppali, the other accused, are allegedly the shooters. The police have not yet been able to arrest the two or recover the murder weapon.
The police said Kumar had confessed to them. They sought custody of the accused to trace the shooters, the vehicle used by the killers, the murder weapon, and the place where the conspiracy was hatched.
Kumar will be taken to Dindigul, Ooty, Chennai, Coimbatore and other places to collect evidence.
The police had sought custody of Kumar for 14 days.
Magistrate Philip Thomas asked them to give up custody as soon as their purpose was complete or after 12 days, whichever happened earlier.