ANCHORAGE, Alaska (AP) — Residents and tourists along Hawaii's coasts are evacuating to higher ground in response to a tsunami warning.

The Pacific Tsunami Warning Center issued the warning for all Hawaiian islands Saturday night, hours after a 7.7-magnitude earthquake rocked an island off Canada's west coast. Hawaii Gov. Neil Abercrombie proclaimed an emergency, mobilizing extra safety measures.

Officials originally said there was no threat to Hawaii but changed that after taking new sea level readings.

Warning sirens blared while residents drove away from coasts and tourists were evacuated from lower floors of beachside hotels. Incoming bus routes were shut off into Waikiki and police shut down a Halloween block party in Honolulu.

The center says the first tsunami wave could hit the islands by about 10:30 p.m. local time (1:30 a.m. PDT Sunday).