Governor Josh Green warns residents not to ‘put yourself in harm’s way’ and readies for possible rescue operations.

Tsunami waves have reached California and Hawaii in the United States following a huge earthquake off Russia’s far east coast.

Tsunami waves breached the US mainland west coast at California’s San Francisco at 1:12am (08:12 GMT) Wednesday, according to the National Weather Service for the San Francisco Bay Area. The tsunami is also impacting the state’s coastal Arena Cove area and making its way further down the coast, the National Weather Service reported.

Further south-west in the Pacific, 1-1.2-metre (3.3-3.9 feet) waves began impacting the US Hawaiian Islands shortly after 8:00pm local time Tuesday (06:00 GMT on Wednesday, July 30), according to the Pacific Tsunami Warning Center

Hawaii’s Governor Josh Green said it is too early to tell how big the waves reaching Hawaii will be, but warned that even small waves are driven with “great force”.

While there have been no reports of damage, he said authorities would wait up to four hours before being able to assess that the situation is safe: “We are not yet in the clear.”

The US National Weather Service also warned “danger may persist for many more hours as wave activity continues.”

“Please do not put yourself in harm’s way,” said Green, adding that Black Hawk helicopters and high-water vehicles were ready to go in case authorities need to rescue people.

Earlier, the US Tsunami Warning Centers had warned that waves as high as 1 to 3 metres (3.3-9.8ft) were possible in Hawaii, while the Honolulu Department of Emergency Management had advised residents of some coastal areas to evacuate.

Hawaii’s Emergency Management Agency said all commercial harbours have been closed. Flights in and out of Hawaii’s second-largest island of Maui were also cancelled Tuesday night, Green said.

The tsunami threat in Hawaii comes as the aftermath of the 8.8 quake in Russia’s far-eastern Kamchatka region – one of the largest on record – puts residents on alert in coastal areas of parts of Russia, Latin America and numerous Asian and Pacific island states.

Waves up to 4 metres (13ft) high have already struck Russia’s far-eastern Kamchatka region, causing some buildings to be submerged. Thousands of citizens in impacted islands have been evacuated.

Japan is bracing for damage as well, with evacuation orders issued for people living along coastal areas or rivers.

Tsunami waves have also been detected by coastal gauges along Alaska’s east Aleutian Islands and the Pacific side of the Alaska Peninsula, according to the US’s National Weather Service (NWS) in Anchorage.

The impact of the tsunami could last for hours or perhaps more than a day, said Dave Snider, tsunami warning coordinator with the National Tsunami Warning Center in Alaska

“In this case, because of the Earth basically sending out these huge ripples of water across the ocean, they’re going to be moving back and forth for quite a while,” said Snider.