Dhaka: Police on Friday sought for 10 days to interrogate the mother of the two siblings who were found dead at their apartment at Banasree in Dhaka on Monday, reports UNB.

Inspector (Operations) Mustafizur Rahman of Rampura police station, also investigation officer of the case, filed an application before the Metropolitan Magistrate Court seeking permission for taking Mahfuza Malek, the mother of the two kids, on police custody for 10 days.

Amanullah, father of the two children, filed a case against their mother Mahfuza with Rampura Police Station on Thursday evening.

Briefing reporters at the RAB headquarters on Thursday, RAB director (Media) Mufti Mahmood Khan said Mahfuza Malek, during interrogation said she strangulated her daughter and son to death with a scarf as she was worried over their future and education.

The RAB director said, ‘We’re now primarily sure Mahfuza killed her two children as she was worried over their future and education.’

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

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.

The family first 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, Obaidul Islam, cousin of Mahfuza, 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.