Russia's Emergencies Ministry says one of its firefighting planes with a crew of 10 is missing in Siberia.
The ministry said the Il-76 plane disappeared Friday while on a mission to fight forest fires in the Irkutsk region. It said that seven aircraft have been searching for the plane, which went missing in the Bayandayevsky district near Lake Baikal.
Officials said the crew hadn't reported any problems before disappearing.
Emergencies Minister Vladimir Puchkov said the search was complicated by heavy smoke from forest fires.
The plane that disappeared is a firefighting version of the Il-76 four-engined heavy transport plane, capable of carrying 42,000 liters (11,000 gallons) of water.