The Police Headquarters formed a probe committee on Monday night, the district's Superintendent of Police Md Mizanur Rahman said on Tuesday.
Brahmanbarhia Police also formed a committee on Sunday night while the district administration formed another on Monday night.
At least 17 temples and over 150 houses have been vandalised and looted in the attacks.
The Police Headquarters committee headed by Chittagong Range Additional DIG Md Shakhawat Hossain already started its work, SP Mizanur said.
It has been given a week to submit a report identifying responsibilities and negligence of officials and making recommendations.
The administrative committee headed by an additional district magistrate has also been given 10 days to submit its report.
Following a Facebook post 'disrespecting Islam' on Friday, tension mounted in Nasirnagar and adjacent Madhabpur Upazila of Habiganj district.
The protesters under the banners of 'Hifazat-e Islam' and 'Ahle Sunnat Wal Jamaat' gathered in a rally in the afternoon in Habiganj district headquarters and Nasirnagar, demanding punishment of one Rasraj Das, who reportedly uploaded the post.
Later on that day, a group of people vandalised at least 15 temples in Nasirnagar and two in Madhabpur. Over 150 houses were also vandalised and looted.
Both Hifazat and Ahle Sunnat denied responsibility for the attacks.