The U.S. Geological Survey reports that a 4.6 magnitude earthquake has rattled the Three Lakes area of Washington state.
That was followed minutes later by a 3.5 magnitude aftershock near the city of Monroe, some 48 kilometres northeast of Seattle.
The initial temblor was recorded at 2:51 a.m. Friday.
There were no immediate reports of damage or injuries.
Some Island and even Lower Mainland residents may have been woken by the quake.
It was lightly felt in Greater Victoria and Vancouver areas, according to Natural Resources Canada.
No tsunami warning or advisories are in effect. No serious injuries or damage have been reported.