The Rapid Action Battalion (RAB) on Thursday said the mother of the two siblings, who were found dead at their apartment in the capital’s Banasree area on Monday, ‘confessed’ to killing them due to her ‘mental problem’ resulting from a family problem.

During interrogation, Mahfuza Maleq alias Jasmine confessed that she had killed her two children at about 5:30pm due to a family feud, said Mufti Mahmood Khan, director (Media) of the RAB Headquarters.

RAB also suspected that Mahfuza might have killed her two children out of insanity, resulting either from a family or social problem, extramarital relationship or over wealth, he said.

RAB on Wednesday detained Amanullah, Mahfuza and Afroza Malek, father, mother and maternal aunt of the two siblings, from Jamalpur district for quizzing them over the mysterious death of the two siblings.

Nusrat Jahan Urmi, 14, a seventh grader at Viqarunnisa Noon School, and her younger brother Alvi Aman, 6, a nursery student at Holy Crescent School in Banasree area, were found dead at their apartment on Monday night.

Family sources claimed that they died after eating refrigerated Chinese restaurant food.

However, the autopsies conducted on their bodies by the forensic department of Dhaka Medical College Hospital found injury marks on the throat of Urmi and on that of Alvi and his one leg.

Police detained four people — Pintu Das and Shaheen, caretakers of the house, victims’ relative Ferdous and house tutor Sheuli Akter — the following day for questioning them over the death.

Besides, a court asked the Criminal Investigation Department (CID) to conduct chemical tests on the food and water taken by the two siblings and permitted police to conduct DNA tests of the evidence, including pillow-cover, bed-sheet, tissue paper and blanket, collected from the room of the two children.