A deadly avalanche hit a school group skiing on a closed slope in the French Alps, killing two students and a Ukrainian skier and seriously injuring three others.
French President Francois Hollande said mountain emergency services with sniffer dogs and a helicopter were engaged in a rescue operation at the Deux Alpes ski resort, 33km southeast of Grenoble.
Officials say the avalanche hit 10 students and a teacher from the Lycee St. Exupery school in Lyon.
A telephone crisis centre has been set up for relatives and friends at the school, which serves over 2,000 middle school and high school students.
Local officials did not give any information on the number of missing but said 60 workers had been mobilised in the search-and-rescue operation, which was being hampered by the dark and the continuing danger of more avalanches.
The regional Dauphine Libere newspaper reported that four of the students were found in cardiac arrest. Officials say the teacher is alive and has been taken to a hospital in Grenoble.
Local councilor Gilles Strappazzon said the avalanche occurred after several groups of skiers dislodged a large snow slab.
The area had been closed off prior to the accident amid high avalanche warnings and it's unclear why the group ventured onto the ski trail.
There had been little snow in the Alps until just after the New Year, so January's steady snow was fresh and possibly less stable.