A strong earthquake has struck at sea 230 miles (375km) south-west of the US Pacific island territory of Guam, the US Geological Survey says.
The 7.2 tremor struck at 2119 GMT on Friday at a depth of 2.9 miles (4.7km).
There was no destructive tsunami threat, the US Pacific Tsunami Warning Center said.
While quakes of this size can affect coastal areas, there were no immediate reports of damage or injuries.
Guam is an important staging post for the US military, allowing rapid access to potential flashpoints in the Koreas and in the Taiwan Strait.