A day after a mob allegedly assaulted an engineering student, Saad Ansari, for “supporting” suspended BJP spokesperson Nupur Sharma, the police registered a criminal offence against the mob late Monday. Of the crowd of 100 to 125 who had assembled outside Ansari’s Bhiwandi home on Sunday, 18 have been identified. The entire mob has been booked for ‘rioting’ and ‘threatening’ under sections of Indian Penal Code. Ansari, who has been arrested, had voiced support for Sharma over her controversial remark on Prophet Mohammed.