The probe committee has submitted an report on Islamic State (IS) caps worn by two death row convicts among seven of Gulshan Holey Artisan Café attack case.
Deputy Inspector General of Police Tipu Sultan confirmed this on Saturday.
Earlier, a probe committee comprising three members has been formed to look into the issue of black caps.
The prison authorities had formed an investigation committee to find out the cause that how the death row convicts of the Holey Artisan Café Attack case got the caps contained IS logo amid the strict security in the court.
According to media reports, the convicts were seen wearing IS caps.