Five Britons, believed to be the members of indie band Viola Beach and their manager, have died in a road crash in Sweden where they staged their first international gig, police said Sunday.

"Five people, all British, died in a car accident Friday night," police spokesman Towe Hagg told AFP, while the British Foreign Office confirmed the deaths of five men aged between 20 and 35.

They died when their car hit a barrier and plunged off a canal bridge at Sodertalje, a southern district of the capital Stockholm.

Their vehicle reportedly approached at speed the bridge which was not fully shut after allowing a vessel to pass underneath in the early hours of Saturday morning.

"First indications are that the barriers and signal lights were functioning correctly," said Hagg.

Other vehicles were waiting for the bridge to close fully but "one car arrived at a crazy speed ... at least 70-80 kph (45-50 mph). That's very quick when everybody else was stopped," Jonny Alexandersson, a lorry driver who witnessed the incident, told Aftonbladet daily.

News of the tragedy spread quickly on social media and fellow band The Enemy tweeted: "RIP Viola Beach and their manager. Such incredibly tragic and sad news. Thought with the friends and families of all involved x."

A contributor to Viola Beach's Facebook page wrote: "So awful. Taken before anybody had the chance to see what they might have become."

Another wrote: "Such sad news, you guys were gonna be big."

The band, who last year had released a debut single, had been in Sweden for a Friday night "Where's the music" festival in the central city of Norrkoping and were headed back to Britain for a gig the following day at Guildford in southern England.

"It was the first time they had played outside of Britain. They were full of hope," festival organiser Folkert Koopmans told Aftonbladet.

"Sadly it seems the four and their manager died in the accident. It's terrible, "Koopmans said.

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