While police in Munich has stated that there is no evidence that the mass shooting on 22 July was a terrorist attack, Islamic State (Isis) has reportedly tweeted in support of the shooting, saying "everything hurting infidels makes us happy". According to Jenan Moussa, a journalist based in the UAE, a propaganda channel linked to the terrorist organisation has been tweeting in support of the shooting, in which nine people died.

Little is so far known about the killer or his motives. Munich police identified the killer as a lone 18-year-old gunman of German-Iranian nationality. But media reports have identified him as Ali Sonboly, although the English-language reports naming him did not state where this information had come from.

The gunman's motive for carrying out the shooting remains "totally unclear". Eyewitnesses to the shooting have said the shooter claimed her had been bullied for seven years.

Details are also emerging that Sonboly used Facebook posts, made using an account he made under the name of Selina Akim, to lure young people to Olympia-Einkaufszentrum (OEZ), the southern German city's largest mall. In the posts, he said a nearby McDonald's outlet was offering free food.

The gunman is believed to have acted alone and is thought to have shot himself after finishing his rampage, leading Moussa to speculate he might not be aligned with Isis (Daesh).

The Mail Online has quoted a handful of unnamed Arabic Twitter accounts which it described as supporting "the radical Islamist movement".

One allegedly wrote: "Thank God, may God bring prosperity to our Islamic State men," and another said, "Whole Europe is now under terrorism."

One employee at the mall described chaotic scenes yesterday, saying: "Many shots were fired. I can't say how many but it's been a lot. All the people from outside came streaming into the store and I only saw one person on the ground who was so severely injured that he definitely didn't survive.

"We have no further information, we're just staying in the back in the storage rooms. No police have approached us yet."