An England fan has died in Sofia ahead of tonight's Euro 2020 qualifier against Bulgaria.
The country's Interior Ministry said the 32-year-old had been found in a 'helpless condition' in the city centre.
Police and an ambulance were called to the spot, close to Borisova Garden.
The fan was taken to hospital for treatment but began to behave 'aggressively' towards staff.
As a result of his 'threatening' behaviour, he was being taken from hospital to a local police station.
It is understood that he died on the journey to the station.
An Interior Ministry spokesman confirmed that the circumstances surrounding his death were being investigated.
"He is believed to have arrived in Sofia to watch the England v Bulgaria match," they said in a statement.
"At 10am, police received reports of a man in a helpless condition in the area of Ivan Vazov and GS Rakovski Streets.
"The 32-year-old was taken by an ambulance team to a hospital for examination, where he suddenly began to behave aggressively, threatening staff.
"As a result of his actions he was being transported to a Sofia police station.
'We are working with the prosecutor's office to establish the facts and circumstances surrounding the incident. "
Local reports said police were investigating whether the fan was under the influence of drink or drugs, but that has not been confirmed.
In another incident before the game, an England fan suffered a broken arm. He was said to have been attacked by Bulgaria fans.
The death came as around 3,400 England fans gathered in bars and cafes around the city centre before last night's Euro 2020 qualifier.
England were beaten 2-1 by the Czech Republic on Friday in another Euro 2020 qualifier. Violence marred the build-up the game when Czech police fired four stun grenades at English fans who had thrown bottles at their vehicles.
Eighteen England fans were detained, and are likely to face football banning orders in the UK.
