The official said it has also issued fresh summons to the TMC Rajya Sabha MP.
"We condemn this incident and sympathise with the families of the deceased. You (Prime Minister Narendra Modi) were aware that such an incident would take place. You had information about this.
Those who had cowered down during the Independence movement are giving sermons on patriotism, O' Brien stated.
On Thursday, West Bengal Chief Minister and TMC supremo Mamata Banerjee said that her party respected the armed forces and did not like politicisation of the sacrifices made by the soldiers.
"India's unemployment rate at a 15-month high of 7.4 per cent in December 2018," he said, adding that "Modi failed to deliver, yet again".
He says Mamata Banerjee has a track record of over four decades of peoples' movements and struggle
O'Brien makes these observations in his book 'Inside Parliament: Views from the Front Row', which is a collection of his political essays
TMC leader's new book talks about the ideal strategy for the Opposition in the next Lok Sabha elections
MoS for Home said no curbs can be imposed on anyone in India where there is freedom of speech