One year after a blast that authorities say was a suicide bombing killed 16 people on a subway car in St. Petersburg, Russian investigators have announced that the probe is nearing completion.
In a statement on YouTube and its official website on April 3, the Investigative Committee said that the case was "currently in the final stage of investigation."
It said the investigation has been "particularly difficult" because "those who ordered this terrorist act, those who organized it, and those who carried it out did not know each other" and used "modern means of communication" to communicate with one another.
Russian authorities say the blast in April 3, 2017, was a suicide bombing carried out by Akbarjon Jalilov, a 22-year-old Kyrgyz-born ethnic Uzbek and naturalized Russian citizen who was among the dead.
In the weeks after the bombing, they arrested 11 people from Central Asian countries in St. Petersburg and Moscow on suspicion of involvement in the attack.
The Investigative Committee said that the bombing, which injured about 50 people, was the work of "a radical Islamist terrorist community" but did not name any group. No organization has claimed responsibility.