Here are 10 facts on the big story:
Prohibitory orders banning large gatherings have been imposed across the state and additional security personnel deployed in the Banda, Mau, Ghazipur and Varanasi districts.
The jailed gangster was rushed to the hospital in Banda after he fell unconscious at a district jail on Thursday night. A few hours later, he was declared dead by the doctors at the Rani Durgavati Medical College.
While the hospital says the cause of death was a cardiac arrest, Mukhtar Ansari's son and his brother have demanded a probe as they believe he was poisoned while in jail.
"Two days ago I came to meet him, but I was not allowed. Despite being unwell, he was sent to jail. If the stomach was bloated then how could there be a heart attack? In the video that went viral, you can see that his stomach was bloated. His condition was serious. He was brought to be admitted to the ICU. But after 12-14 hours he was sent back to jail," his son Umar Ansari told the media.
A panel of five doctors will conduct the postmortem today. A large force of police personnel has been deployed outside the Banda hospital where Mukhtar died.
Ansari, who hailed from Mau, was believed to have a strong influence in the adjoining Ghazipur and Varanasi districts as well. A large crowd has already gathered outside the former Bahujan Samaj Party (BSP) MLA's house in Ghazipur.
Uttar Pradesh Director General of Police Prashant Kumar that as a precautionary measure, Section 144 of the CrPC has been imposed across the state.
Central Reserve Police Force has also been called in to assist the police. CRPF units have already been deployed in Banda, Mau, Ghazipur, and Varanasi.
The social media cell of the Uttar Pradesh Police is also on high alert to track "unlawful elements" that may try to spark a riot.
Mukhtar Ansari was a former five-time MLA from Mau Sadar seat and had 60 criminal cases pending against him. He was sentenced in eight cases since September 2022 by different courts of UP and was lodged in the Banda jail.
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