A Wales football supporter died on Tuesday following a fight before his country's Euro 2012 qualifier against England at Wembley Stadium in London, Metropolitan police said.
Six people, all Welsh, were arrested over the incident after police were being called to the stadium's concourse at 19:20 (18:20 GMT) following reports of an assault.
Paramedics attended to a 44-year-old man, who had head injuries, but he was pronounced dead after being taken to a north London hospital.
The man was also suffered a cardiac arrest outside the stadium, a spokesman for the London Ambulance Service said.
Homicide officers are investigating the death and a post mortem will take place shortly.
An Ashley Young goal handed England a 1-0 win to leave them six points clear at the top of Group G.