Blood stains were visible on the streets along with bodies covered in blankets in the aftermath of the incident in Drottninggatan, a street in a busy shopping district.
Paramedics could also be seen tending to the injured near the lorry, which was embedded in the corner of the Ahlens department store with its cab burning.
Watch | People seen running after truck crash in Stockholm00:58
The attack comes after trucks were used in terror attacks in Nice and Berlin last year and just two weeks after Muslim convert Khalid Masood ploughed his car into pedestrians on Westminster Bridge in London.
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