A foreign national in his 40s has been arrested in Sweden for allegedly photographing restricted sites in Stockholm and Sundsvall.

The man, reportedly a Russian citizen, was detained in Karlskoga over the weekend.

He was found intoxicated at a local festival and in possession of a knife.

Subsequent searches revealed a drone and other equipment in his hotel room, indicating he had taken photos of protected sites.

He has been remanded in custody, suspected of breaching security laws.