Haryana Home Minister Anil Vij told the Assembly on Monday that a CBI probe will be announced in connection with the killing of the Indian National Lok Dal's (INLD) state unit chief, Nafe Singh Rathee.

Vij also denied the opposition's charge that the law-and-order mechanism has collapsed in the state.

"If the House is only satisfied with a CBI probe, then I assure the members that we will hand over the case to the CBI," Vij said while speaking on an adjournment motion moved by the Congress over Haryana's law-and-order situation.

Speaker Gian Chand Gupta admitted the adjournment motion as the Congress demanded a high court judge-monitored CBI probe into Rathee's killing.

Soon after the Question Hour, the Congress members raised the issue of Rathee's killing and demanded a discussion on law and order.

Rathee and an INLD worker were killed when unidentified assailants sprayed their sports utility vehicle (SUV) with bullets at Bahadurgarh, near Delhi, on Sunday.

The attack, which came with less than two months to go for the Lok Sabha polls, drew sharp reactions from the opposition parties in the BJP-ruled state.

Twelve people, including former Bharatiya Janata Party (BJP) MLA Naresh Kaushik, were booked on Monday in connection with Rathee's killing, police said.

Vij told the Assembly that police are properly probing the incident, but when Leader of Opposition Bhupinder Singh Hooda said the case might involve various angles that can only be investigated by a central agency, the home minister said a CBI probe will be announced.

Congress leader Raghuvir Singh Kadian asked the speaker to allow a discussion on the adjournment motion moved by his party.

The speaker admitted the adjournment motion after which the House discussed the issue.

Kadian described Rathee's killing as the state's "first political murder" and demanded a high court judge-monitored CBI probe into the incident.

His demand was backed by Hooda.

Kadian also said Rathee was not given a security cover despite the fact that he was facing threats.

Vij described Rathee's killing as a very sad incident.

"I immediately directed the officials concerned to take action. I spoke to the DGP, the Jhajjar SP and the head of the STF, and directed them to catch the culprits at the earliest," he said.

Vij said the registration number of the car is being verified.

On the opposition targeting the BJP over the alleged breakdown of law and order, he said, "It is being said that the entire law-and-order system has broken down in the state, which is not true." Those behind Rathee's killing will not be spared and exemplary punishment will be given to them, the home minister said.

Earlier, paying homage to Rathee when the House was condoling his death and that of former Lok Sabha speaker Manohar Joshi, Kadian said the INLD leader's death was not natural.

"It is a political murder and the first one in Haryana since it was carved out as a separate state (in 1966)," the Congress leader said.

Chief Minister Manohar Lal Khattar led the House in paying tributes to Rathee.

Kadian said Rathee came from a farmer family and rose to become an MLA after a lot of struggle in life.

"We demand a high court judge-monitored CBI probe into the incident," he said.

Kadian said Rathee was facing threats to his life and had sought a security cover for himself. "The question that arises is, why security was not provided to Rathee," he added.

Since the FIR lodged in connection with the incident has named some accused with a political background, it is a "political murder", the Congress leader claimed.

Hooda said even in the past, many MLAs had faced threats, while Congress leader B B Batra said a "sense of insecurity is prevailing among the state's citizens".

"The circumstances are such today that every citizen in Haryana is feeling insecure. Even MLAs in the past have faced threats. If our state is unsafe, then development cannot take place, no investment will come," Hooda said.

Senior Congress leader Kiran Choudhary said, "Haryana's law and order is worse than Uttar Pradesh and Bihar.... A state of fear has gripped the state after the incident (Rathee's killing)." Congress leader Geeta Bhukkal said, "Criminal elements have become so emboldened that traders are getting threats and incidents of killing and other heinous crimes have become common. Haryana has become unsafe as law and order has broken down." Congress's Neeraj Sharma alleged that the government is busy monitoring the activities of the MLAs, instead of giving top priority to their security.

Congress member Kuldeep Vats said there have been instances in the past when MLAs received threats, while his party colleague Jagbir Malik described Rathee's killing as a serious incident. "Tomorrow, it can be anyone amongst us," Malik said.

Haryana has never witnessed political murders, said Aftab Ahmed, the Congress MLA from Nuh.

Khattar had on Sunday said not a single culprit in the case will be spared. Police have been instructed to arrest the accused as soon as possible and take strictest action, he had added.

Senior INLD leader Abhay Singh Chautala accused the BJP-JJP government of failing to provide security to Rathee, despite there being a threat to his life. He also demanded a probe by the Central Bureau of Investigation (CBI) into the incident.

The Aam Aadmi Party (AAP) has also hit out at the Khattar government over the incident.

Except for the headline, this story has not been edited by The Telegraph Online staff and has been published from a syndicated feed.