Some reports suggested he had previously posted jihadist propaganda on his Facebook page and had images of people injured in the explosion at the Boston marathon in April 2013.
Police found explosives in the truck used in the attack in Stockholm, Swedish television said on Saturday citing multiple unnamed police sources.
Stockholm attack: ‘Homemade bomb’ found in lorry used to kill at least four people in Sweden
A homemade bomb has reportedly been found in the lorry used to kill at least four people in Stockholm.
Police sources told public broadcaster SVT the device was found in a bag, and had not been detonated, adding that the attacker had “burned himself”.