Swedish security forces continue investigating Friday's truck attack, which killed four and injured 15.
In the attack, the terrorist ploughed into crowds in a shopping area in central Stockholm, Sweden.
According to Swedish police, the suspect is a 39-year-old father of four from Uzbekistan. Police also said they found explosives in the truck used for the ramming attack.
On his Facebook page, the suspect published ISIS-related materials, including pictures of 2013's Boston Marathon terror attack.
Following the attack, all flags in Stockholm were lowered to half mast.