An analysis of a mysterious substance seized on Friday by customs agents in Malmö confirmed it was the toxic compound potassium cyanide, newspaper Expressen reports.

The suspicious powder was taken during a search in connection with a criminal investigation regarding drug trafficking. The powder was stored in a can.

Anette Malmberg of the Customs Service press office told the newspaper that it's uncommon to find such a dangerous substance during a police search.

"As long as it is in a jar, there is no problem. But of course it is very risky for...