A volcano in the Philippines has reportedly erupted, spewing rocks and ash and killing three foreign climbers and their guide.

According to local reports four climbers and guides remain missing on the Mayon volcano, in the central Philippines, which had been calm for three years.

Guide Kenneth Jesalva told ABS-CBN TV network by cellphone from a camp near the crater that the climbers died after being hit by huge rocks.

AP quotes him as saying that another man was critically injured from a group of eight that included five foreigners and three Filipino guides. The nationalities of the foreign climbers are not yet clear.