After primary investigation, the law enforcers have found that the killers were known to the five victims murdered at their house in Baburail area of Narayanganj on Saturday.
The investigators are now assessing records of previous enmity with the family over financial transactions and sexual harassment among other issues to unearth the mystery behind the murders.
Meanwhile, bodies of the five deceased were handed over to the family members yesterday after conducting post mortem examinations.
Doctors said the killers first wanted to suffocate the victims, but later confirmed death by hitting their heads with heavy blunt objects. The deceased had several marks of injuries on their bodies. Police had initially said the victims were slaughtered.
The killings took place on Saturday, confirmed Dr Asaduzzaman of Narayanganj General (Victoria) Hospital. A three-member board conducted the post mortem yesterday afternoon.
Officials of the Criminal Investigation Department, who collected evidence and samples from the bodies and the spot, said they would be able to find the exact number of killers after examining those.
Meanwhile, Shafiqul Islam, husband of murdered Taslima Begum, registered a lawsuit with sadar model police against some unnamed people around 11:30am yesterday, OC Abdul Malek said.
The case was later handed over to the Detective Branch of Police.
Three people have been detained for questioning. They are Delwar, Shahadat and Mahfuz.
Police recovered the bodies of Taslima, 35, her daughter Sumaiya, 7, son Shanto, 10, brother Mosharraf alias Morshed, 20, and sister-in-law Lamia, 20 on Saturday evening based on information given by their relatives. The main gate of the flat on the ground floor of a six-storey building was found locked from outside.
Family and police sources said Mahfuz, a niece of Shafiqul, used to make indecent proposals to Lamia. At one point, Mahfuz was sent to Dhaka but the harassment continued. Later, Mahfuz took a job in Narayanganj and started to harass her again. After Lamia disclosed the matter to her family, they rebuked Mahfuz and beat him up.
According to the case, Taslima had borrowed Tk12 lakh from Nazma and Shahjahan of Kalabagan. They used to visit the family in Narayanganj and issue threats as Taslima had failed to pay the monthly instalments in time.
Plaintiff Shafiqul also said his brother-in-law Mosharraf had borrowed money from some local businessmen. They used to visit the house to collect money and often engaged in altercation.
Building owner Ismail Hossain, who returned from the USA three months back, also said he had heard noise at the flat during the visit of the lenders.
Rahima Begum from the adjacent flat said she had not heard anything unusual from the flat on Saturday. “I do not know who locked the gate after the murders,” she said.
Senior police officials including Director General of Rapid Action Battalion Benazir Ahmed, DIG (Dhaka range) Mahfuzul Hoque Nuruzzaman and Narayanganj Superintendent of Police Khandaker Mahiduddin visited the crime spot yesterday morning.
Benazir said the elite force had already started a shadow investigation into the heinous killings. Family conflict could be a possible reason behind the murder, he said, adding that they could not confirm whether the killers were professional.
DIG Mahfuz said they would apply every scientific method to identify the killers from the samples including fingerprints.
“After primary investigation, we think that the killers were known to the victims from the past. They killed the two children not to keep any eyewitness,” he added.
Ehsan Uddin Chowdhury, CID’s assistant superintendent of police, said the victims had been suffocated and left unconscious before being killed.
The CID also collected breads and other foods from the spot. Ehsan thinks that the killers might have fed the victims the foods adulterated with sedatives before killing them.
