They burnt all the documents just before a SWAT team stormed the flat in Taj Manzil, locally known as Jahaj Bari.
Those documents could have helped the police with the investigation and perhaps led to the patrons of those militants, said Additional Commissioner Monirul Islam, chief of Counter-Terrorism and Transnational Crime (CTTC) unit of the DMP.
“However, we still have some leads in the investigation, which are being analysed now,” he told the Dhaka Tribune.
Facing imminent death, the nine militants took photographs wearing the so-called Islamic State attire before the operation, police sources said. They found the photos from the electronic devices recovered from the den.
Police suspect that the militants put on the black panjabis and keffiyehs following Fazr prayers, sensing that the police might move in after daybreak.
Saiful Islam, acting deputy commissioner at the CTTC unit, said that they recovered several laptops and other devices in which they found some information.
In the raid, police also arrested one suspected militant while another managed to flee.
Requesting anonymity, a CTTC official told the Dhaka Tribune that the evidence as well as the information gleaned from detained militant indicated that the militants had been planning to attack places where foreigners work or socialise.
The police are now looking for Tamim Ahmed Chowdhury, the alleged mastermind of Gulshan attack who is also suspected to have visited the Kallyanpur den.
Another source in DB police told the Dhaka Tribune that they were carrying out raids in several areas of Dhaka to arrest militants who might have set up more hideouts in bachelors’ hostels.