An anguished Irani told the media after the cremation of Surendra Singh, the victim, that she will also knock on the Supreme Court's door to ensure that the culprits got death sentence.

Irani rushed to Amethi from New Delhi and took part in the funeral of Surendra Singh, a former head of Barauliya village who was shot by bike-borne assailants outside his house, along with Uttar Pradesh Minister Mohsin Raza and scores of party supporters.

Both Raza and Irani helped carry the body of the deceased on their shoulders.

Singh was taken to the district hospital in Amethi after the attack and then referred to Lucknow. He succumbed to his injuries while on his way.

The post-mortem of the deceased was carried out in Lucknow after which the body was brought to Amethi for cremation.

Director General of Police O.P. Singh said that seven suspects had been detained in connection with the murder who were being interrogated.

He said the police had got crucial leads. Three companies of the Provincial Armed Constabulary (PAC) had been deployed in Barauliya village where the murder took place.

BJP sources said that Singh had actively worked for Irani during the general elections.

Police teams conducted raids in adjoining villages to trace the accused.

Surendra Singh's son Abhay told reporters: "We could not see the perpetrators but it is clear that Congress workers are behind this. My father was actively campaigning for Smriti Irani and the BJP."

The brother of the deceased, Rajendra Singh, also termed it a political killing. He said his brother wielded considerable influence in his village as well as in the adjoining villages and this led to his murder.

Minister Raza, who is in-charge of Amethi, said the killers would be arrested within 24 hours.

Raza added that the government will ensure such stringent punishment for the assailants that no one will dare to target BJP workers in future.

"No one will dare to harass and target our workers. We will ensure strict punishment for the killers. At the moment we are all with the family of the deceased," he told reporters.

Senior police officers from Lucknow reached Amethi to supervise the investigation.

Barauliya, the village to which Surendra Singh belonged, is said to be a BJP stronghold and sources say the Bharatiya Janata Party (BJP) got votes from here even when Congress President Rajiv Gandhi held the Amethi seat.

Surendra Singh, interestingly, had joined the Samajwadi Party on the eve of the 2017 Assembly elections but returned to the BJP soon after.

The deceased was preparing to contest the panchayat elections scheduled to be held later this year and this could have been a motive behind the murder, some said in Amethi.

On May 24, a Samajwadi Party member of the zila panchayat, Vijay Yadav, was shot dead in Ghazipur.