Another three earthquakes have struck off Shetland a day after parts of the Scottish isle and northern Scotland were shaken by a tremor.
The latest quakes measured 2.7, 2.5 and 2.2 magnitude and occurred between 2.29am and 9.51am on Tuesday, according to the British Geological Survey.
The were in the same area as a tremor, which measured 5.1 magnitude, occurred at 5.32am on Monday and 112 miles north-east of Shetland.
In total five quakes have now been recorded off Shetland in two days.
Earthquakes can come in clusters. An earthquake swarm is a sequence of seismic events occurring in a local area within a relatively short period of time.
The BGS said that Monday’s quake was felt in Shetland, Aberdeen, Ellon, Stonehaven, Helmsdale, Inverurie, Lairg, Huntly, Banff and Fraserburgh.
It said that reports described: “lying in bed and heard a low rumbling sound”, “three waves of vibration in about three seconds”, “it woke me up as windows rattled”, “bed shook and windows creaked”, “mirror rattled” and “felt it as well as heard it, enough to wake me up”.
In January a significant earthquake measuring 3.6 in magnitude was recorded in the North Sea, in an area of oil and gas platforms.
It struck around 146 miles east of Aberdeen.
It is not yet clear if any of the recent quakes were also felt by any rigs.
A 6.1 magnitude quake hit the North Sea in 1931 and another in the area measuring 5.1 was recorded in 1958.