In a fresh crackdown on SIMI activists in Madhya Pradesh, three persons were taken into custody in connection with the Mumbai bomb blasts, police said on Friday.
The three, including known SIMI activist Imran Ansari, a close confidant of top functionaries of the banned outfit, were held for interrogation by the crime branch police, they said.
Though police refused to divulge the nature of interrogation, they were ascertaining whether the activists were linked to Mumbai train blasts.
Ansari's suspected involvement in some criminal cases in Surat and Kanpur was also being probed, they added.
Police had tightened the noose around SIMI after the blasts, rounding up nearly a dozen of its suspected activists from Bhopal, Indore, Khandwa, Burhanpur and Ujjain districts.
"No formal arrest was made as most of them were released after interrogation," the sources said, adding that more people were expected to be held and efforts were on to trace known office-bearers of the banned outfit, most of whom have gone underground.
Even as operations against SIMI intensified, senior police officials chose to keep mum over the investigations.
Conclusive evidence to link SIMI activists with Mumbai blasts was yet to be found, even though a prankster was arrested two days ago for sending an e-mail to a newspaper office about the attack, they said.
Another person was held on Friday for allegedly sending an e-mail in the name of Lashkar-e-Qahar to a TV channel, the sources said.