A British serviceman was found dead after a night out in Stockholm.
The 25-year-old arrived in Sweden for the Aurora 23 defence exercise which ran from April 17 until May 11.
The serviceman, who was with the Plymouth-based HMS Albion ship, was reportedly on a night out with other members of the Armed Forces when he died.
A murder investigation has been launched following his death and four people have been arrested.
A murder investigation has been launched following his death and four people have been arrested
PA
The Ministry of Defence has confirmed that it is aware of the incident and is “assisting local authorities in their investigation”.
The Briton ended up at a house in Solna along with several people from Sweden on the night he died, according to Swedish newspaper Expressen.
It also claims that among the four people arrested is another British serviceman and three Swedes, aged in their 20s and 30s.
A spokesman for the Royal Navy said: "We are aware of an incident in Stockholm and we are assisting local authorities in their investigation.
"It would be inappropriate to comment further."
The Aurora 23 defence exercise is where thousands of servicemen and servicewomen practice countering an attack on Sweden.
It was conducted on the ground, in the air and at sea, and it was a huge national exercise.
HMS Albion led the Littoral Response Group (North) (LRG) into the Baltic Sea for Exercise Aurora.
Speaking about the Aurora 23 defence exercise, NATO said: "Exercise Aurora is a Swedish national exercise with international participants, including NATO members.
The Ministry of Defence has confirmed that it is aware of the incident
PA
"The exercise is an important opportunity working towards collective security in the region which sees participants practicing against high intensity scenario replicating potential threats.
"The exercise will include fighter, transport and other support aircraft from Sweden, Finland, Poland, Portugal, the United States and the United Kingdom.
"Operating from bases in Sweden and around the Baltic Sea area missions flown throughout the exercise will train air defence, including both offensive and defensive air operations, Intelligence, Surveillance and Reconnaissance operations as well as close air support and strike missions."
