“The photographs of cars shown in the email match the ones stolen from Navi Mumbai for terror activities,” Joint Commissioner of Police, ATS, Hemant Karkare, said.

Preliminary investigations show that the senders hacked into the WiFi facility of the college, said Additional Commissioner of Police (ATS) Parambir Singh. The senders deleted their log entries immediately after using the network, he added.

The Indian Mujahideen had earlier used an unprotected WiFi network at the Navi Mumbai residence of American national Kenneth Haywood to send an email to news organisations on July 26, only five minutes before the Ahmedabad explosions.

The email was sent from an id created just six minutes before. The router in question is located in the college's computer centre on the mezzanine floor.

“The logs were remotely accessed. Though the logs were not disabled, the entries were deleted after the email was sent. This is making the probe difficult,” said Singh.

The ATS, which has seized router and some computers for forensic probes, is also closely following up with service provider VSNL and will also approach Google for details of the account.

The email before the Ahmedabad blasts was sent from a Yahoo account.

The college management, meanwhile, informed ATS that around six students were using the computer centre at the time the email was sent.