The United States national, from whose Internet Protocol address a threatening email was sent prior to the Ahmedabad [Images] serial blasts, and at least eight others have undergone brain mapping and lie detector tests, a senior Anti-Terrorism Squad official said on Wednesday.

"Ken Haywood, along with eight to ten other suspects, has been sent for lie detector and brain mapping tests," Additional Commissioner of Police (Anti-Terrorism Squad) Param Bir Singh said.

The tests were conducted at the Forensic Science Laboratory in Kalina, he said.

                                                     'It could have happened to anybody'

The official, however, refused to reveal the identity of the other persons who were taken for the scientific tests.

Heywood's residence in the Sanpada area of Navi Mumbai was raided by ATS officials on July 27, after the IP address from which a threatening email was sent minutes before the Ahmedabad serial blast, was found to be his.

ATS officials had also seized ten other computers from houses neighbouring Haywood's residence, which had been sent to the FSL and an interim report had been received, the official said.

                                                    Coverage: Ahmedabad Blasts

The interim report suggests that the email was not sent from any of the hard discs seized, Singh said, adding that investigations were still on in the matter.

The police suspect that Haywood's insecure wireless Internet connection was used to send the email.

All the tests had been conducted on the persons with their consent and all of them, including Haywood, had voluntarily submitted to it, Singh said, adding that Heywood had been co-operating with investigators.

There has been no headway in the investigations of the cars stolen from Navi Mumbai which were used in the blasts, he said.

Four cars were stolen in the span of a week from Navi Mumbai about a fortnight prior to the blasts in Ahmedabad. Two were used as car bombs in the serial blasts while two were found unexploded in Surat [Images].

                                Haywood's computer may not have been hacked: Cops