"It is among the poorest governed state in the country. Our immediate concern is law and order," said Chidambaram.
"For the last two to four months, I have repeatedly informed the state chief minister and his colleagues about the deteriorating law and order. He was in denial but the bubble burst after Netai happened. The Netai incident provided the proof of violence by armed cadres of CPI-M (Communist Party of India-Marxist)," he said.
Nine people, including four women, were killed and 28 injured in the clashes triggered by assailants allegedly backed by the ruling Marxists in Netai near the Maoist stronghold of Lalgarh in West Midnapore district Jan 7.
"I lay the blame at the doors of the Communist Party of India-Marxist (CPI-M), which helps its cadres to procure arms and indulge in violence, turning the state into a killing field," he said.
"I sincerely hope that after the change of power in Bengal, both the centre and state governments will work together to restore peace, law and order and stop killing," Chidambaram said.
He said in most cases Trinamool supporters were at the receiving end.
"The CPI-M is the ruling party. It is in the government, so it is their obligation to maintain law and order situation in the state," he said.
Describing West Bengal as one of the debt-stressed states where the tax-GDP ratio is lowest among the larger and general category states, Chidambaram said: "The state's cash position is precarious, and during 2010-11 it has taken overdraft on seven occasions, and during 2011-12 it has already taken one."
Chidambaram also scoffed at expelled CPI-M leader Somnath Chatterjee contesting Prime Minister Manmohan Singh's allegations about the lack of development and educational backwardness of West Bengal, and said the former Lok Sabha speaker's heart was not in the campaign.
"We hold Somnath 'babu' in high esteem. I think his heart is not in the campaign. I think he is doing out of a sense of duty for a party with which he was associated," Chidambaram told reporters here.
Describing the CPI-M as a party which still does not have the "honesty" to admit its mistake, the minister said Chatterjee has not produced any facts and figures and numbers which could contradict the prime minister's statements.
"If you ask me for more numbers, I am willing to give you more numbers that will establish the prime minister's statement was absolutely correct. I do not think that there was anything in the prime minister's statement which was contrary to the facts," he added.
Chidambaram also felt that the change may be painful to some extent.
"An Indian Police Service officer joining the state as a junior officer retired as the top most officer under the government of same party. It only happened in West Bengal not in other state of the country," said Chidambaram.
"It will take very deft handling to bring the change," he said.
When asked how he could be so sure that the new government will be able to restore peace and law order in the state, he said: "I am very optimistic. The new government with new policies, fresh thinking and fresh energy...will restore law and order, rejuvenate the economy."
"My optimism is justified or not will be proved later," said Chidambaram.