The Crime Branch CID, investigating the murder of 13-year-old Dilson in the defence residential complex here on Sunday, is likely to subject a few suspects to lie detector tests, sources in the agency said on Friday.

Investigators recorded statements of a Lieutenant Colonel and a soldier, who were allegedly present in the complex at the time of firing.

“Police are working on some clues that may lead to the identity of the accused. We are also recording statements from others present on the campus on that day. Once prima facie evidence is made out, we may subject the suspects to lie detector tests after taking their consent,” a senior police official said.

Director-General of Police K. Ramanujam inspected the scene of firing on Friday and held discussions with the General Officer Commanding Major General Jamwal. “The defence residential complex is a secured place where outsiders or unauthorised persons cannot have easy access. On the face of it, it appears that an insider is involved…the Army is extending good cooperation in the investigation,” Mr. Ramanujam said. Additional Director-General of Police (CBCID) R. Sekar said the forensic and ballistic report indicated that the weapon used was a self-loading rifle or something similar.