- We see a system in wanting to harm others, says Nils Norling, the police's press spokesperson. 

It was 12.40 on Wednesday, when a woman called the police. She had found broken glass in the sand below the swings at a playground on Kungsgatan in Malmö.

The police have investigated the place, but just like in the other cases, they have little to go on. 

Calling for witnesses

- We have nothing to work on and would like to receive witness information from the public, says Nils Norling. 

The police count a total of about 30 cases of broken glass since January. In different places spread all over Malmö. 

Wednesday's event is classified as causing danger to others. 

A few days ago, SVT reported that a three-year-old girl injured her foot, after she stepped on a broken glass bottle in Beijers park. 

- There is a connection between many of the events. Someone has studied placed glass with a sharp edge, where children jump off swings, says Nils Norling. 

Under a layer of sand

Sometimes the glass has been visible, sometimes it has been under a layer of sand. On a couple of occasions, a rejected glass bottle has protruded from the sand. 

Nils Norling appeals to parents to check carefully, before letting children loose on the playground. 

- It must not continue like this, that children risk injuring themselves when they play in a sandbox, says Nils Norling.