A lot of extensive work has been done to find where the thermos come from, according to the police.
"We have to do everything to find out where the thermos are coming from," says chamber prosecutor Therese Stensson, preliminary investigator in the case about the unusual grip in a press release.
At the press conference on Friday, police and prosecutors will tell more and show pictures of the thermos they want help with tracking.
It was a police patrol who, during an ongoing drug investigation, conducted a house search in an apartment in central Gävle. When they found an object they did not know what it was.
The object was photographed and photos were sent to the bomb squad of the National Operational Department NOA. The apartment was blocked off and the bomb squad came there.
A total of six people were suspected in the investigation. Two people are now detained, the remaining four are released. The suspected crime is classified as preparation for the general destruction of the property.