Mr Behera, who visited the house of the Dalit woman, said a scientific probe has been launched to nab the culprits involved in the crime.
"We are doing the investigation. Investigation is not like magic. A scientific probe has been launched to nab the culprits," he told reporters in Perumbavoor.
Noting that the probe into the sensational case was progressing well, he said it might take some time to nab the criminals.
Facing flak over the delay in arresting the people involved in the crime, Behera said in some cases arrests can be made in 24 hours but in some cases it may take at least a year to arrest the culprits.
The Director General of Police also met the victim's mother who is admitted in a Government Taluk Hospital in Perumbavoor.
He also held a meeting with the recently constituted investigation team headed by ADGP B Sandhya and other officers at the Aluva Police club.
The LDF government in one of its first decisions appointed senior woman police officer Sandhya as the head of a new team to probe the case.
The Kerala High Court had last week rejected the plea for a CBI probe into the case noting that a new Special Investigation Team had been set up in the case.
The woman, who hailed from a poor family, was allegedly raped and brutally assaulted using sharp-edged weapons before being murdered at her house on April 28.
The murder was in focus during the Assembly polls campaign with political parties attacking the then UDF regime for "tardy" progress in the investigation and failure to nab the culprits.
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