RAB detained the four suspects, including a relative of the victims, from the district’s Nalitabarhi on Wednesday evening, its spokesman Mufti Mahmud Khan told bdnews24.com on Thursday.
Sujata Chiran, 40, and her mother Besset Chiran, 65, were found dead on Tuesday in their flat on the third floor of the building in the Kalachandpur neighbourhood in Dhaka.
Khan, speaking at a news briefing later, identified the four suspects as Sujata’s nephew Sanjib Chiran, 21, and his friends Raju Sangma, 24, Probin Sangma, 19, and Shuvo Chisim, 18.
Raju works at a hotel in Dhaka and the three others at a rice mill in Sherpur, according to the RAB official.
He said Sanjib and his friends had planned to steal money from the flat to spend in Easter Sunday.
They searched the flat for money when Sujata passed out after a few drinks but could not find any, he said, referring to information given by the four suspects during initial interrogations.
Sujata’s mother Besset returned home in the evening and caught the four searching the flat, the RAB director said.
The suspects got angry at getting no money in the flat and when Besset asked them what they were looking for, they strangled her with a scarf.
They also killed Sujata by slitting her throat, Khan added.
Sujata’s husband Ashis Mankin started a case against the four people on Wednesday.
Gulshan Police Station OC Abu Bakr Siddique told bdnews24.com Sanjib and his three friends were seen entering and leaving the house on a CCTV camera.