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Doctors at the Lucknow hospital where the teen is admitted, said she has extensive fractures on her ribs, collarbone, an arm and a leg. She is in a critical condition and on ventilator.
"It was not an accident but a conspiracy to eliminate all of us... The son of a co-accused in the case, Shahi Singh, and another youth of the village had threatened us," the teen's mother was quoted as saying by news agency Press Trust of India. "I have got to know that the lawmaker got it done. He is doing everything from inside jail," she said.
At a press conference on Monday, the police said they have arrested the truck driver and the owner. The number plates, the owner allegedly said, were defaced to stop identification of the vehicle as he had defaulted on the payments for the vehicle loan.
The teen, the police said, was assigned nine security personnel, including a gunner. The gunner, Suresh, told NDTV that the security personnel were asked to stay back as "there was no space in the car". "Aunty said there was nothing to worry about since five people were going and that they would be back by evening," he said.
About the girl's mother's claim that the family was being threatened by Kuldeep Sengar and his men, the police said, "We are inquiring whether this was the case. They had security with them. We are looking into whether they had said this to the police".
The family, residents of Unnao - around 45 km from state capital Lucknow - was on its way to the district jail in Rae Bareli on Sunday to meet her uncle, who is serving a life term in a separate case. Amid a heavy downpour, their car had a head-on collision with a truck, which, eyewitnesses said, was speeding.
Kuldeep Sengar - a four-time legislator who represents Bangermau in the Uttar Pradesh Assembly - has been in prison for a year over the alleged rape, which took place in 2017. The girl alleged that she was sexually assaulted by the lawmaker when she went to his Unnao home to seek a job. Kuldeep Sengar's brother Atul Sengar has been accused of murdering the girl's father, who was pursuing the case.
The case made it to national headlines after the girl and her mother attempted to immolate themselves in front of the house of Chief Minister Yogi Adityanath last year. The girl's father, who was arrested and accused of illegal arms possession, died in police custody. Before the arrest, he was beaten up by Atul Sengar and his men. Postmortem report showed extensive injuries.
The matter created ripples in parliament, where the upper house, Rajya Sabha, was adjourned till noon following Opposition protests. The National Commission for Women is taking cognizance of the Unnao rape case and Sunday's accident. The Commission said it is writing to the Uttar Pradesh Police and a team will visit them shortly.
In a series if tweets, Congress's Priyanka Gandhi targetted the state's BJP government led by Yogi Adityanath. "So a woman is allegedly raped by a BJP MLA. Her father is beaten up and dies in custody. A key witness dies mysteriously last year. Now her aunt who was also a witness is killed and her lawyer is critically injured in an accident caused by a truck with blackened number plates... The accused continues as a BJP legislator, and the BJP State Government has the audacity to run a 'Fear-free UP' campaign???"