Swedish terrorism expert Magnus Ranstorp from the Swedish National Defence College says he doesn't think the suspected terrorist was working alone.
Speaking to Swedish Television news, Ranstorp says the blasts were too complicated to have been planned and executed alone. Tabloid reports that a car bomb as well as pipe bombs were used, a backpack full of nails was found next to the body, and that a warning message was sent to a news agency and Sweden's Intelligence Service in both Swedish and Arabic, indicate that the plans were more complex than originally thought.
"This isn't something someone does in their living room and plans completely alone", Ranstorp told SVT, "but whether the others are in Sweden or abroad is another matter" he adds.
"If it's true that he had a backpack full of nails which was supposed to explode and cause maximal damage, and he was moving towards areas where people were doing their Christmas shopping, it could have caused an enormous massacre if he had succeeded. But a lot went wrong."