World sprint champion Falla recorded a time of 3min 15.55sec to beat Sweden's Jonna Sundling by 0.48.

Nadine Fähndrich of Switzerland claimed a surprise bronze after finishing third in the final.

Johaug was bidding to become the first woman to win six straight World Cup races since legendary Norwrgian Marit Bjørgen earned seven in a row between December 2014 and January 2015.

But the 10-time world champion, who in 2016 served an 18-month drugs ban, failed to reach the final.

Johaug remains in charge of the race for the overall World Cup crown and has 1,918 points, 579 ahead of nearest challenger and compatriot Heidi Weng.

Norway's Johannes Høsflot Klæbo edged closer to overall leader Alexander Bolshunov of Russia with victory in the men's sprint.

The reigning Olympic and world champion led a Norwegian sweep of the podium on home snow to claim a record-extending 23rd sprint World Cup success.

Klæbo clocked 2:52.07 to win the final, crossing the line 1.20 ahead of Pål Golberg.

Erik Valnes was a further 0.40 adrift in third place.

Victory for Klæbo, who has now won each of the last 15 individual sprint World Cup events he has appeared in, moved him to an overall total of 1,374 points.

The Norwegian still has a mountain to climb if he is to overhaul Bolshunov and secure the overall crown as the Russian is 458 points clear in first place.

Bolshunov was unable to extend his advantage at the summit after making the semi-finals but failing to reach the race for the gold medal.