Director General of Police K Ramanujam stated this in his counter to a Habeas Corpus Petition filed by the child's mother in court.
The DGP said only one of the six CCTV cameras installed was functioning and photo prints developed through it were also not clear. The video recordings were taken to Chennai for image enhancement, but the feedback was not satisfactory.
He claimed six of 10 cases of child lifting since 2006 had been detected and the remaining were being investigated.
The DGP said investigation relating to lifting of the child last year had been geared up and even small clues and insignificant information was being followed up. So far 20 suspects and 110 witnesses have been questioned.
More From This Section
The case has been transferred to the city crime branch and will be monitored personally by the Commissioner of Police, the DGP said.
On June 14 last year, a 35-year-old woman had kidnapped the baby after introducing herself to the mother as a nursing assistant and telling her the infant should be kept in an incubator and that her mother and mother-in-law instructed her to do so.