Twenty members of staff at Swedish state agencies were decontaminated after white power was sent to the agency that collects debts.

On Tuesday the power will be tested to see whether it is, in fact, dangerous.

The envelope was first opened at the Tax Agency (Skatteverket) in the southern city of Malmö, and fifteen people have been treated for possible contamination. The opened envelope was then sent on to the Kronofogden debt agency and five people have been treated after discovering the powder.

Four police officers were also treated.

The public health agency Folkhälsomyndighetens will now analyse the powder.

The...