A series of tremors continued for around 24 hours.

Minor tremors are common around the Mt Hood volcano, which is located near to Portland, Oregon, with around three recorded every week within a 10 kilometre radius of the volcano.

But for 63 in just 24 hours is extremely rare and could be a sign that an eruption is on its way.

A spate of small tremors around a volcano usually signifies that magma and gasses beneath the surface are beginning to navigate their exit.

Portland State University Geology Professor Emeritus Scott Burns told KATU News: “If you get swarms under a working volcano, the working hypothesis is that magma is moving up underneath there.”

The tremors began on Sunday and continued into the beginning of this week.

The massive volcano, which reaches a height of 3,429 metres, has experienced four major eruptions in the last 15,000 years, but three of those have come in the last 1,800 years.

The last major one occurred in 1782 and erupted for almost two decades.

The news follows on from a similar announcement regarding St Helens volcano in Washington, where a spate of tremors have also been felt.

Professor Burns continued: “It just reminds us that we live in a geologically active area. Volcanoes do occur periodically.

Source: VOLCANO WARNING: Scores of tremors at Mt Hood signal it may be about to BLOW | Science | News | Daily Express