The instructions on bomb making must have been detailed, TV4 News reports.
Already, two men, believed to have been involved in radicalizing Akilov and helping him with the terrorist act, have been arrested. The men have never been identified by Swedish police.
For a few years now, one of the men has been presumed dead - but a new review by several media shows that he appears to be alive in a Syrian prison.
The text is updated.