The Delhi Police on Wednesday said the probe in the rape threats to Delhi University student Gurmehar was being carried out in a professional manner and that some more time would be needed to crack the case.

"We are trying to identify the culprits. The Crime Branch and Cyber Cell are simultaneously investigating the case. A comprehensive inquiry is on and we need some (more) time to crack it," Special Commissioner of Police Deependra Pathak said.

He said the police investigation is based on Gurmehar's complaint and a screenshot that the Delhi Commission for Women forwarded along with her complaint to the Delhi Police.

The police have sought the help of Facebook and Google search engine to track the IP addresses from which the threats emanated, he added.