(CNN) -- A magnitude 6.6. earthquake struck Tuesday off Canada's Pacific coast, the U.S. Geological Survey said.
The strong quake hit about 339 kilometers (211 miles) south of Metlakatla, Alaska, and about 667 kilometers (414 miles) west-northwest of Vancouver, British Columbia, the USGS reported.
It struck about 7:30 a.m. (10:30 a.m. ET), the USGS said.
A second quake, apparently an aftershock, struck in the same area minutes later, according to the USGS. That temblor had a magnitude of 5.7.
No damage was immediately reported.