The boy, identified as Rabbani Khan alias Taj, was picked up from his maternal grandfather’s house in Ashiar Gagan under Jhalakathi Sadar on Sunday, following a tip-off, said Joint Commissioner of Detective Branch (DB) of Dhaka Metropolitan Police, Nasirul Islam, at a press briefing.

The victims were identified as Mariam Begum and Sufia Begum.

Briefing reporters at the DMP media centre on Monday afternoon, Nasirul said, Taj left his rented house in Shanir Akhra at around 12:00 pm saying his mother that he was going for private tuition. Instead, he went to his elder aunt Mariam Begum’s rented flat in West Shewrapara under Mirpur police station by a CNG auto-rickshaw at around 12:50 pm.

While his elder aunt was preparing lemon juice for Taj and his younger aunt was cleaning dishes on the veranda, he allegedly stole Tk 3,000 from a wallet kept near the TV in a room. When Mariam caught him in the act and scolded him, he stabbed her in the abdomen with a lemon-cutting knife. As she attempted to fight back, he stabbed her again.

Hearing her screams, another aunt Sufia rushed from another room, but Taj stabbed her once as well.

He then allegedly took a pestle from the kitchen and struck both women multiple times on the head, killing them on the spot.

He later cleaned the blood from his body in the bathroom, changed his bloodstained clothes with his cousin sister’s jeans and a t-shirt, wore a cap, and locked the main gate of the flat from outside before leaving, saif the joint commissioner.

He took a CNG-run auto-rickshaw to travel to Shanir Akhra, discarding the house keys and cap on the road. He paid Tk 450 as fare and threw away the remaining stolen money due to bloodstains.

At a local shopping centre, he changed back into his pink panjabi and disposed of the bloodied clothes through a ventilator in a washroom. He also threw his shoes onto an abandoned building near his house.

On May 10, the day after the incident, he left for Jhalakathi to attend the burial of one of the victims.

Joint commissioner Nasirul further said the boy had been closely monitoring law enforcement activities and had attempted to evade arrest by moving between locations.

Finally, the detectives identified Taj scrutinising video footage of the Shewrapara building. Later, they arrested him.

Replying to a question, the joint commissioner DB said that Taj revealed that he had stolen Tk 3,000 to buy a bycycle.

Further investigation is underway to determine if he was under the influence of drugs or acted under someone’s influence, he added.

Acting on his confession, police recovered the bloodstained clothes from a sewer near the shopping centre and his discarded shoes from the abandoned building. One of the recovered jeans belonged to his cousin.