Siddhartha Das and Mugdha Das, two suspects arrested in connection with the killings of former schoolteacher Ganapati Chakraborty, his wife and their two children in Rangpur, have been taken to Dhaka for DNA sample collection.

The two accused were taken to the forensic laboratory of the Criminal Investigation Department (CID) in Dhaka on Sunday night, said Deputy Commissioner (Detective Branch) of Rangpur Metropolitan Police Sonaton Chakroborty.

DNA samples of the two accused will be collected at the CID laboratory and compared with biological samples and other evidence recovered from the crime scene and the victims, he said.

Various pieces of evidence have been collected from the scene and the DNA testing will help determine whether any biological evidence found there is linked to the two accused, he added.

However, investigators said no conclusion can be drawn until the DNA test results are available.

On August 22, the bodies of Ganapati, 65, a former teacher of Rangpur Zilla School, his wife Pritilata Chakraborty Bala, 50, daughter Agami Chakraborty Prarthi, 25, and son Ayush Chakraborty Priyam, 12, were recovered from their locked home in Machhuapara of Rangpur city.

Police said all four were strangled to death.

Police arrested Mugdha, 23, and Siddhartha, 19, from the same area the following day in connection with the killings.

The two arrested suspects later gave confessional statements under Section 164 of the Code of Criminal Procedure before a court, while two witnesses, identified as Shimanto and Bidyut Das, also gave statements before the court.