The Anti-Terrorism Squad in Mumbai has traced the fifth threatening email sent after the Ahmedabad [Images] blasts allegedly by an outfit Indian Mujahideen [Images] to a suburban college in Mumbai.

"This was the fifth threatening email sent after the Ahmedabad blasts and has been traced to the Khalsa college in the central suburb of Matunga," Additional Commissioner of Police (ATS) Parambir Singh told PTI.

The email has been traced to the computer laboratory of the college, which holds around 20 computers, Singh said.

"It will have to be checked if this email too was sent through a wireless router like in the case of Kenneth Haywood," Singh said.

Earlier, the ATS had traced the fourth threatening email to a residence in the Sanpada area of Navi Mumbai, owned by US national Haywood.

The ATS after preliminary inquiry had stated that the email had been sent through Haywood's computer's IP address, which might have been hacked into.

Ten computers from neighbouring houses and Haywood's residence were sent to the Kalina Forensic Science Laboratory for analysis.

"Similarly, all the computers in the lab of Khalsa college might be sent for analysis," Singh added.