A 2,900-metre high volcano in Kamchatka the Russian Far East erupted on Thursday night, spewing ashes and gas up to nine kilometres above sea level, the Russian news agency Interfax reported from Petropavlovsk-Kamchatsky.

It said a volcanological station had registered numerous explosions at the Bezymyannyvolcano, located in the central part of Kamchatka peninsula.

The head of a team responsible for flight safety during eruptions told the agency that an cloud of ashes over 100 kilometres in length was moving to the northeast and could pose a threat to aircraft on international routes near Kamchatka.

A warning had been sent to the volcanological observatory in Alaska, the official said.

Experts say the eruption poses no immediate threat to the closest communities - Klyuchi 50 kilometres away and Kozyrevsk 30 kilometres away.

The 2,869-meter-tall volcano, which last erupted in May, is one of the most active in Kamchatka, the agency said.

An eruption by the volcano in 1956 was "one of the three most significant volcanic events on the globe this century".

BBC Monitoring (http://www.monitor.bbc.co.uk), based in Caversham in southern England, selects and translates information from radio, television, press, news agencies and the Internet from 150 countries in more than 70 languages.