Police have identified the first four bodies of people who were killed in a fire at a bar in a Swiss ski resort on New Year’s Eve.

The bodies of two Swiss women aged 21 and 16, and two Swiss men aged 18 and 16 have been returned to their families, police said.

“Extensive” work from officers and the Institute of Forensic Medicine made the identifications possible, Valais cantonal police said in a statement, and work to identify the remaining victims continues.

The blaze at Le Constellation in Crans-Montana killed 40 people and injured 119 others, officials have said. With many of the injured identified, families now face an agonising wait for information about those still missing.

The likely cause of the fire was sparklers on champagne bottles being carried too close to the ceiling, a preliminary investigation of how the fire began found.

Switzerland’s President Guy Parmelin called it “one of the worst tragedies” experienced by the country.

Further details about the identified victims, including names, have not been released.

Among the dead and missing are many teenagers. Le Constellation was a venue known to be popular with a younger crowd in the ski resort town, where the drinking age is 16.

On Friday, police said 113 of the injured have been identified, and include 71 Swiss, 14 French and 11 Italian citizens.

A teenage golfer from Italy was the first death to be named, though Swiss and Italian officials have so far declined to confirm his death.

A helpline has been set up for concerned families: +41 848 112 117