Karimganj Deputy Commissioner Debeswar Malakar today ordered the inquiry into the incident. The report of the inquiry is to be submitted within 15 days, official sources said.
In another development, three personnel security officers of the MLA were suspended due to dereliction of duty.
"The PSOs had failed to protect Nath and her second husband and had fled from the spot when the mob barged into the hotel where the duo were staying", the sources said.
Nath, who represents Borkhola constituency in Cachar, and her second husband were beaten up and injured on Friday night in a hotel here by a group of people who were angry over her second marriage without divorcing her first husband.
Violent protests by supporters and opponents of the controversial MLA have been going on in Barak Valley since the last three days.
Prohibitory orders under section 144 of the CrPC were imposed in Cachar, Karimjang and some parts of Hailakandi district to prevent untoward incident.
Five persons were arrested for the assault on the MLA.
Six minority organisations have today declared a 24-hour bandh at Badarpur in protest against the attack on the MLA. A 12-hour bandh has been called at Borkhola.
The Vishwa Hindu Parishad, the RSS and the Hindu Jagran Manch have called for a day-long bandh in the entire Barak Valley on July 24.
