Four people - a British national, two Swedes and one Belgian - were killed in the Islamic terrorist attack on Friday.
Markus Krantz, 37, and his girlfriend who live just north of the capital went to the scene of the attack after it was re-opened to the public, and noticed that nothing was there to recognise the death of the dog called Iggy.
When it came to light that Iggy was a rescue dog, Markus returned to the scene and left the dog flowers and a message on their behalf.
The original image posted by Markus on Saturday from the scene of Iggy's death - which has over 48,000 reactions - shows dog crackers, candles and a leash that belonged to his dog Ebba who died in 2016.
Markus told the BBC that he and his girlfriend heard that a dog had been killed but were unable to find anything where Iggy last walked that specifically recognised the dog.
"We decided to put down flowers and dog crackers, and light a candle," he said.
"My mom asked me to take a picture and send it to her and since it went online, the response has been 100 per cent positive. Just pure love," Markus continued.
Following this, Markus discovered that Iggy was a rescue dog from Dogs Aid Animal Sanctuary in Dublin. Markus currently has five dogs, all rescued from Romania.
Dogs Aid asked Markus to return to the site and leave a message on their behalf: "Iggy Run Free, from all ur friends in Dogs Aid in Dublin."
On Facebook, the sanctuary said: "We are deeply saddened to learn that one of our dogs was killed in the terrorist attack in Stockholm. DOGS AID IGGY found his beautiful home in Sweden in 2012."
More people have paid a visit to the memorial site. Pictures online show a stuffed dog, a child's drawing of a dog, crackers, a rubber dog bone toy, candles and flowers.
And Facebook users sent their love to Iggy, with one sharing an image of "doggy heaven".
(BBC - April 10, 2017)
