Russia's emergency situations ministry said today it was dispatching experts to a Siberian province to find out why yellow and orange snow has been falling in several villages, the ITAR-TASS news agency reported.

"A chemical test unit will be sent to Omsk ... it's main task will be to investigate pollution in the region and establish the degree of danger represented by the anomalous snow fall," the agency quoted an unnamed official from the ministry as saying.

Snow ranging in colour from light yellow to orange and carrying a distinctive "musty" odour was observed yesterday in five districts of Omsk province, which lies in western Siberia and borders Kazakhstan, ITAR-TASS said.