TOKYO--At least eight people have died in an earthquake that struck Japan on New Year's Day as authorities on Tuesday struggled to assess the full extent of a disaster that wrecked buildings and roads and left thousands without power in freezing temperatures. The quake with a preliminary magnitude of 7.6 struck in the middle of the afternoon on Monday, prompting residents in some coastal areas to flee to higher ground as tsunami waves about 1 metre (3.3 ft) high hit Japan's western seaboard. A thousand army personnel have been dispatched to the worst-hit area in the country's relatively remote Noto peninsula, but rescue operations have been hindered by badly damaged and blocked roads and one of the area's airports has been forced to close due to runway cracks. Many rail services and flights into the area have also been suspended. "The search and rescue of those impacted by the quake is a battle against time," Prime Minister Fumio Kishida said during an emergency disaster meeting on Tuesday in remarks aired on television. "We must rescue them as quickly as possible, especially those who are trapped under collapsed structures." Public broadcaster NHK said eight deaths had been reported in the hard-hit town of Wajima near the quake's epicentre, while in nearby Suzu some doctors were unable to reach a hospital that was relying on a backup generator for power. The national police said agency six people had been confirmed dead. More than 90 tremors have been detected since the quake first hit on Monday, according to the Japan Meteorological Agency. The agency has warned more strong shocks could hit in coming days. In Toyama city, around 100 km (60 miles) from the worst-hit area, some shelves in convenience stores were empty as the disaster disrupted the delivery of goods across the region. Four expressways, two high-speed rail services, 34 local train lines and 16 ferry lines were halted, while 38 flights have been cancelled since the quake hit, according to the transport ministry. President Joe Biden said in a statement the United States was ready to provide any necessary help to Japan after the earthquake. "As close allies, the United States and Japan share a deep bond of friendship that unites our people. Our thoughts are with the Japanese people during this difficult time," he said. The Japanese government said as of Monday night it had ordered more than 97,000 people in nine prefectures on the western coast of main island Honshu to evacuate. They were spending the night in sports halls and school gymnasiums, commonly used as evacuation centres in emergencies. Almost 33,000 households remained without power in Ishikawa prefecture early on Tuesday morning, according to Hokuriku Electric Power's 9505.T website. Most areas in the northern Noto peninsula also have no water supply, NHK reported. The Imperial Household Agency said it would cancel Emperor Naruhito and Empress Masako's slated New Year appearance on Tuesday following the disaster.