KANPUR, June 3 -- A married couple has been arrested for the murder and dismemberment of a 20-year-old man after investigators found a meticulous digital trail on their smartphones, including YouTube queries on how to evade capital punishment, dispose of a corpse, survive a police encounter, and even prison amenities, police said on Tuesday. The victim, Vijay Nishad, had been missing from Fatehpur district since May 8. His family lodged a missing person's complaint on May 11. During analysis of his call detail records, Bakewar police noticed unusually high call volume between Nishad and a woman named Kiran Devi, a resident of neighbouring Hamirpur. When the couple - Kiran and her husband Kamta Prasad Nishad - were picked up, sharp inconsistencies emerged in their accounts, police said. A forensic examination of their mobile phones then revealed the incriminating search history, which became the pivot in solving the disappearance. According to SP, Fatehpur, Abhimanyu Manglik, the homicide was rooted in an extramarital affair between the victim and Kiran Devi. "On May 8, Kiran lured Vijay to her house where Kamta bludgeoned him with a wooden door frame," Manglik said. "They then used a grinder machine to sever the limbs, packed the remains into a sack, and drove to a forest area in Kanpur's Reuna where they incinerated the body using petrol to erase all clues." Vijay, who frequently visited Kiran's village to meet relatives, had allegedly leaked compromising photographs of her on social media following a dispute. The images reached Kamta while he was working as a labourer in Gujarat, forcing him to quit his job, return home, and plan the murder with his wife. The victim's family, however, has contested the police theory that the couple acted alone, saying several villagers had witnessed Vijay being assaulted by a larger group on the night he vanished. They also argued that Kiran is currently pregnant, and that Kamta walks with a medical iron rod embedded in his leg, making it implausible for just two people to dismember, transport and dispose of a body without external logistical help....