A 14-year-old boy choked his younger sister to death in Dhaka as he thought the parents used to cherish, love, and take care of her more than him, said the Rapid Action Battalion (RAB).
According to the elite force, sibling jealousy provoked the boy to kill his four-year-old sister Mim. He later dumped the body in a bathroom, said RAB-1 Assistant Director Kamruzzaman told The Business Standard.
Earlier on Wednesday, Nusrat Jahan Mim's body was found at Banani's Jamai Bazar slum in Dhaka. The father Liton Mia subsequently filed a murder case with Banani police station.
During investigation, RAB detained the brother Thursday morning. In primary questioning, the fifth-grader at a local school told RAB that he thought his parents' love for him started to wane after his sister was born.
The father Liton Mia, a street vendor hailing from Narsingdi's Shingnapur village, said he and his family have been living at a rented room at the slum for the last four years.
Liton said he and his son went to deliver goods to a person living nearby on Wednesday morning, leaving Mim at home alone as her mother had already set out for work.
"After the delivery, my son returned home and I went to my work," he added.
RAB said the boy strangled his sister to death while she was asleep and hid her under the bed after returning home on Wednesday morning. He then dumped Mim's body in the bathroom next door.
After returning home, the parents started searching for their daughter as the girl was there. Later, Mim's body was found at a common bathroom of the slum around 10 am.
"We could not believe that my son killed her sister," the father said.
Lt Col Ashique Billah, director of RAB Legal and Media Wing, told the press that the parents' love and care for the boy declined since the birth of his younger sister Mim.
"The father often beat up the boy for nothing. And one point, he started to blame his younger sister for that. Returning home every day, the father used to call the girl first and adore her," he added.
Quoting the boy, the RAB official also said that the parents had fulfilled all the wishes of his younger sister, but the opposite happened to him.
"He desired the same love and care his younger sister got. For this, began waiting for an opportunity to remove the girl so that the parents care him as they did before the birth of Mim," said the RAB official.