All these riots were blots on the country for which all Indians were ashamed, Kumar said and asked those responsible for the carnage to own up responsibility.
Nobody could escape accountability for these incidents, the chief minister told reporters.
Kumar slammed the RJD-led government headed then by Lalu Prsad for closing the investigation in the Bhagalpur riots case after assuming power in 1990, despite the facts that there were material evidences available to bring the culprits to book.
It was his government that pursued the Bhagalpur riots case and brought the culprits to justice, besides providing assistance and relief to the victims and pension to the those displaced in the incident, Kumar said.
Kumar also trashed Congress Vice-President Rahul Gandhi's defence of a likely alliance with the RJD for the forthcoming Lok Sabha elections and said that there was a world of difference between what the leader says and does.
"There is a huge difference between what (Rahul) Gandhi says and does... Even the public understands as much and will not buy his clarification on his party's alliance with the RJD in Bihar," Kumar told reporters.
Observing that the alliance between the Congress and the RJD was a natural one as the latter had been part of the UPA-I and also supported UPA-II from outside, Kumar said that he would have been baffled if the pre-poll alliance between them would not have come through.
"Given the similarity of thinking and behaviour of the two parties, the alliance between the Congress and the RJD is a natural one," the chief minister said.
Kumar, a senior JD-U leader, also took the Congress vice-president to task for his remarks on not compromising on corruption and said that the Congress' leader's stand runs against the grain of the UPA government.
He also blamed that because of the rise in corruption and price rise during the UPA rule at the Centre the Congress's support base has declined over the years.
He said that the Congress Vice-President cannot get away by washing his hands of the price rise and corruption dogging the country during the UPA government's two terms as people would hold him accountable for their miseries.
"(Rahul) Gandhi will have to own up responsibility for not only the price rise and corruption during the UPA governments, but also for the work culture of its regime that allowed these problems to fester much to the chagrin of the masses," he said.
The JD-U leader also found inconsistency in Rahul's strident opposition to an ordinance to bail out convicted lawmakers and help them retain their elected seats which the UPA government subsequently withdrew.
Asked on JD-U's possible alliance with any party in the forthcoming Lok Sabha elections, Kumar said that his party may contest the polls on its own.
"The JD-U will most likely contest the general elections on its own as we have not spoken to any party regarding the alliance," he said.
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