Sweden's Riksbank has filed a police report after a ransomware attack on software firm Tietoevry knocked out some of the central bank's IT systems.
Riksbank's human resources and payroll systems have been inaccessible since an attack on Tietoevry's data centre in Sweden nearly a week ago, according to Bloomberg.
The attack, which has affected a host of Tietoevry clients, was carried out by the Akira ransomware gang.
In an update on Thursday, Tietoevry said: "Overall the customer-specific situations vary greatly, for example in terms of the solutions in question, customer-specific workloads and the volume and complexity of related data restoration.
"A restricted number of customer situations will require additional restoration actions that are being planned in close dialogue with those customers."
Ransomware attacks have been on the rise in recent months, with securities lending trading platform EquiLend warning clients this week that services could be down for several days after it was hit.