Two cousins were arrested for allegedly killing a 73-year-old woman and her daughter and looting their valuables in Krishna Nagar in east Delhi, police said on Sunday.
They said the accused carried out the murders under "Mission Malamal", ostensibly aiming to become rich.
The two have been identified as Kishan (28) and his cousin Ankit Kumar Singh (25), both natives of Siwan district in Bihar, police said.
Kishan was presently living in Laxmi Nagar here, they added.
Singh is a singer and has a music band. He was composing lyrics and music for an upcoming film on over-the-top (OTT) platform, police said.
Bodies of Rajrani (73) and her daughter Ginni Kirar (39) were found in a highly decomposed state and maggot-infested in Krishna Nagar on May 31, according to the police.
Police said the accused had contacted two advocates to seek legal advice before committing the crime.
It is suspected that they got influenced by web series where they learnt how the police works. However, nothing concrete can be said at this point of time as the matter is under investigation, they said.
On Wednesday, a person made a PCR call at 7.56 pm about a foul smell emanating from a flat on the first floor of a building in Krishna Nagar's E Block, following which a police team rushed to the spot.
Bodies of Rajrani and Kirar were found lying the house, which was ransacked.
During investigation, police analysed over 200 cameras of entry and exit routes of accused persons. The accused were seen entering a house after committing the crime. Police raided and found that it belonged to the prime accused, Kishan, Deputy Commissioner of Police (Shahdara) Rohit Meena said.
However, Kishan had come to know that the bodies of the women have been found and fled the house, he added.
Call detail records confirmed that the mobile phones of the victims as well as that of the accused were latched to the same tower in Lucknow, Uttar Pradesh, after the murders on May 25, the DCP said.
The accused switched off their mobile phones when they got to know that the police were chasing them, he said.
They were planning to flee to Bihar and then to Assam. Police traced the location of Ankit Kumar Singh near BD Estate, Timarpur, and subsequently nabbed him, Meena said.
The movement of Kishan was traced in Lucknow. He later came to Delhi and was apprehended from the Kanti Nagar area while he was preparing to surrender before the court, the DCP said.
Interrogation revealed that Kishan, who was working as a marketing manager in a firm dealing with medical equipment, got himself registered in a website offering online tutor service. He got in touch with Rajrani who needed a computer tutor for her differently-abled daughter, Ginni Kirar, Meena said.
Kishan started going to the house of Rajrani from April for tution of her daughter and slowly gained the trust of the women as they wanted to shift from the area and he helped them search a house in Lajpat Nagar. They shared account details for online payment with him and he found that they had over Rs 50 lakh in the bank account. He made a plan to kill them and keep the money, the DCP said.
Initially, the accused tried to transfer money from the victims' bank accounts to some other accounts, but they were unable to do so as the net banking and ATM facility was not available in those accounts, police said.
Thereafter, they planned to loot the victim and named their conspiracy as "Mission Malamal" on WhatsApp on May 17.
To execute the 'mission', accused Singh came to Delhi from Assam, where he was attending his sister's marriage, a day before the incident and did a recee of the area and purchased knives from Laxmi Nagar, police said.
Meanwhile, Rajrani was looking for another tutor for her daughter and Kishan introduced Singh to her. When Rajrani agreed, Kishan sent a message to Singh that "Mission Malalmal is on", they said.
The victims had installed a video screen system in their house and nobody would enter the place without them allowing it. On the day of the incident, the accused got a friendly entry in the house around 9.50 pm. They were expecting a huge cash and jewellry in the house, police said.
One of the accused asked Ginni for water and the moment she went inside the kitchen, they cut Rajrani's throat with a knife and then also attacked Ginni in a similar fashion, the police said.
The blood splashed in the house and the accused cleaned it as well as themselves to remove the evidence. They ransacked the house and escaped with valuable items, including an idol assuming that it was made of gold. Singh changed his T-shirt that had blood stains before leaving the house. They locked the door from outside and fled around 11.10 pm, police said.
A video has also emerged in which the accused can be seen coming out of the house after committing the crime.
The accused also took the video screen system from the house of the victim and disposed off it in Gonda, police said, adding Singh also received deep wounds during the incident crime.
The accused went to Lucknow where they again tried to transfer the money from the accounts of the deceased but could not succeed, police said.
After the incident, they started their normal lives as Kishan planned a trip with office colleagues and Singh started singing again, police said.
Singh earlier offered singing coaching in the New Ashok Nagar area, they added.
He is a science graduate and has taught in many schools in Bihar. He lost his job in March, they said.
Two bags used in crime, two Apple laptops, one Dell laptop, two chargers, three iPhones, one bag of Ginni, blood-stained clothes worn by the accused persons during the commission of crime were recovered from them, police said.
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