Here are 10 developments in this big story:
This was the first time that Ashish Mishra was summoned for questioning amid calls for his arrest by opposition leaders - the violence that erupted in Lakhimpur on Sunday has turned into a major political issue months before the state elections. The cops posted summons outside Ajay Mishra's home for the second time today.
Union Minister Ajay Mishra today said his son was "innocent" and will appear before police tomorrow. "We have full faith in law. My son is innocent. He got a notice on Thursday but he said he was not well. He will appear before the police tomorrow and give his statement and evidence as he is innocent," the junior Home Minister was quoted as saying by news agency PTI.
Eight people, including four farmers, died in the UP district on Sunday after a car ran over a group of demonstrators protesting against the visit by junior Home Minister Ajay Mishra and UP's Deputy Chief Minister Keshav Prasad Maurya.
Ajay Mishra was asked to appear for questioning at 10 am yet top cop Upendra Agarwal - who is heading the eight-member probe team - kept waiting for him, officials said. He was named in an FIR filed by the farmers who have demanded strict action against him.
Ajay Mishra, the FIR said, drove into the gathering of protesting farmers amid a peaceful black flag protest. "The incident took place around 3 pm, when Ashish Mishra with his three vehicles along with 15-20 men with weapons moved towards Banwaripur meeting place... Ashish, sitting on the left side of his Thar Mahindra, fired at the crowd. The vehicle mowed into the people... Due to the firing, farmer Sukhvinder Singh's 22-year-old son Gurvinder died," reads the FIR.
Former Chief Minister Akhilesh Yadav, Congress leaders Priyanka Gandhi Vadra and Rahul Gandhi, among others, have alleged the police are shielding the high-profile accused.
Two people - Luv Kush and Ashish Pandey - were arrested on Thursday as the case reached the Supreme Court. They were reportedly in the same vehicle that ran over a journalist and farmers, the police said.
"Summons have been issued to Ashish Mishra and he has been asked to come for questioning soon as possible and more action against him will follow," Lakshmi Singh, the Inspector General of Lucknow Zone, told NDTV on Thursday. "We are not shielding anyone. The law of the land is equal for all. We will ensure that strict action is taken," Lakshmi Singh said. Thirteen people are named in the case.
The Supreme Court, which is hearing a petition linked to the Lakhimpur Kheri violence, on Thursday questioned "how many people have been arrested" A day after it was asked to submit a report, the state government this afternoon said it is ensuring an impartial probe.
While Ajay Mishra and his son have denied that they were present at the spot, demands have been raised that the Union Minister should step down. The minister earlier this week told NDTV that the SUV - which has been seen in viral videos running over protesters at top speed - belonged to his family. After his meeting with Home Minister Amit Shah, sources, however said, his resignation has been ruled out.