The man, aged 25, was a British citizen and had been on a night out at the weekend with another British colleague after the Aurora 23 exercise – Sweden’s biggest military exercise since 1989 – ended on May 11th, Swedish tabloid Expressen reports.

He and his colleague ended up at an apartment in Solna, northwest of central Stockholm, with a group of Swedes.

Three Swedes have been arrested on murder suspicions along with his British colleague. All of the suspects are in their 20s or 30s.

The Swedish Prosecution Authority told Expressen that preliminary investigations are under way and confirmed the arrest of four suspects, although they were unwilling to provide more information on the event or details of the suspects.