OSLO -- Three individuals died and four others sustained serious injuries after a long-distance bus veered off highway and plunged into a lake in Hadsel, northern Norway, local authorities said on Thursday.

The bus carrying more than 50 passengers was on its way from Narvik to Solvaer when it overturned in Hadsel, near Raftsundet, in Lofoten archipelago, northern Norway's famous tourist destination. Emergency responders faced challenging conditions at the site, including adverse weather that hampered helicopter operations.

"The bus is partially underwater. Three fatalities have been confirmed, and four people are seriously injured," said Bent Are Eilertsen, chief of staff at the Nordland Police District. "Emergency services have evacuated everyone from the bus."

The seriously injured victims were airlifted to a hospital, while others were taken to nearby shelters, including a school.

Authorities confirmed the passengers on board are from eight different countries, including Norway, India, China, Singapore, Malaysia, the Netherlands, France and South Sudan.

The Chinese Embassy in Norway confirmed that about 20 Chinese tourists were on the bus, among whom five suffered minor injuries. The embassy said it is maintaining contact with the tourists and will provide necessary support to ensure their safe departure.

Norwegian Prime Minister Jonas Gahr Store expressed condolences over the deaths. "I think everyone in Norway is affected by what we are now hearing from Hadsel," he told national broadcaster NRK, urging the nation to stand with "those who are so badly affected."

An investigation into the circumstances surrounding the crash is underway.