By Annika Breidthardt
ROSA KHUTOR, Russia (Reuters) - The Olympic biathlon men's 15km mass start at the was postponed to 1530 local time (11.30GMT) on Monday due to poor visibility after heavy fog descended on the Laura centre for a second day, organizers said.
The race was originally scheduled for Sunday evening but organizers pushed it back to Monday morning.
"Officially, if the weather improves, it will be 3.30pm but there will have to be some improvement," a spokesman for the local organizers told reporters.
Biathlon combines cross country skiing and rifle shooting. Athletes have to complete a distance over skis and stop at a shooting range two or four times depending on the disciplines.
As thick fog covered the mountains the view of the targets - 50 meters from where athletes stand or lie - was completely wiped out on Monday.
France's Martin Fourcade, who has already claimed two gold medals in Sochi, and Norway's Ole Einar Bjoerndalen, who is looking to secure a record-breaking 13th Winter Olympics medal, are among the favorites for the mass start.
It was the third time that a biathlon race at the Olympics has been postponed.
At the Nagano Games in 1998, the men's sprint was called off after heavy snow and fog forced the race to be stopped and be started again the following day.
In Sapporo in 1972, the same scenario applied to the men's 20km individual.
(Reporting by Annika Breidthardt, editing by Mitch Phillips)