Police and others search a stone spa where an avalanche occurred, in Senboku, Akita Prefecture, on Feb. 2. (Mainichi)

TOKYO (Kyodo) -- Heavy snow and blizzards hit areas along the Sea of Japan on Wednesday, with the weather agency warning of continued heavy snowfall through Thursday to Friday.

More than 4 meters of snow had accumulated in Aomori city's Sukayu hot spring area by Wednesday, while some areas of Yamagata and Niigata prefectures had snow over 3 meters deep, the Japan Meteorological Agency said.

In Semboku, Akita Prefecture, three people were found in a state of cardiac arrest after they were caught in an avalanche while taking a bedrock bath at a hot spring inn, and all subsequently died.

Etsuko Kusakai, 63, from Yokohama, Yuzuru Saito, 59, from Semboku, and Yoko Masukawa, 65, from Tokyo, were confirmed dead later, the police said.

Snow is leveled after being transported to the bed of Jinzu River in Toyama Prefecture on Feb. 1, 2012. (Mainichi)

Three tents set up for the bedrock baths on the premises of the Tamagawa Onsen inn were crushed and covered with snow to a depth of about 1.5 meters, according to the police and the inn.

According to the Akita Local Meteorological Observatory, snowfall of 115 centimeters was recorded at an observation point near the inn as of 6 p.m. Wednesday.

Winds measured up to 132.48 kilometers per hour in Sakata, Yamagata Prefecture, 116.64 kph in Cape Erimo in Hokkaido, 109.80 kph in Akita, the capital of Akita Prefecture, and 101.88 kph in Sado, Niigata Prefecture, the weather agency said.

In Aomori Prefecture, several hundred vehicles were stranded on Route 279 after a 40-km section from Nobeji to Mutsu was closed as a truck and a bus could not ascend a slope at the town of Yokohama amid snowstorm around 5 p.m. Wednesday, causing a traffic jam, according to local authorities. There were no reports of injuries.

Early Thursday, Aomori Gov. Shingo Mimura asked the Maritime Self-Defense Force to send a disaster relief mission, while the town offered refuge to some 150 people stranded within the cars by opening nearby schools and assembly halls.

The weather agency said that snowfall will peak Thursday and continue through Friday along Sea of Japan coastal regions from northern to western Japan, as well as in mountain areas on Shikoku Island.

A man removes snow around a vehicle in Yuzawa, Niigata Prefecture, on Wednesday, Feb. 1, 2012. A storm coming in over the Sea of Japan brought snow and wind to Japan's west coast Wednesday. (AP Photo/Shizuo Kambayashi)

Up to 80 cm of snow is expected in the 24 hours through Thursday evening in the Tohoku and Hokuriku regions, 60 cm in the Kinki and Chugoku regions, 50 cm in the Kanto-Koshin and Tokai regions, and 20 cm in Shikoku.

The agency also warned of high waves of up to 8 meters through Thursday in the sea off northern Japan and the Hokuriku region on the Sea of Japan side of central Japan.