TOKYO - A massive typhoon, bringing heavy downpours and winds, made landfall on Japan's main island of Honshu on Saturday evening, while the country remains at its highest alert level after an unprecedented emergency warning was issued for Tokyo and six prefectures.

The weather agency issued an emergency warning over Typhoon Hagibis ahead of its landing on the Izu Peninsula before 7 p.m., saying heavy rainfall "with a level of intensity observed only once every few decades" is predicted in Tokyo and the prefectures of Gunma, Saitama, Kanagawa, Yamanashi, Nagano and Shizuoka.

Japan was at its highest alert level as the typhoon threatened to sweep through Tokyo, with over 3 million advised to evacuate, train operators suspending most services and airports shut down in the metropolitan and surrounding areas.

Typhoon Hagibis, meaning "swift" in the Philippine language Tagalog, could dump amounts of rain not seen since a deadly typhoon in 1958, the Japan Meteorological Agency said.

It is the first time the agency has issued the warning, the highest on a one-to-five scale, for Tokyo and the six prefectures.

Japanese authorities warned that the typhoon is causing water levels in a number of rivers, including the Tama and the Arakawa in the metropolitan area, to rise dangerously.

The projected path of the typhoon may result in further damage to areas in Chiba Prefecture near Tokyo where another powerful typhoon destroyed houses and triggered widespread power outages in September.

Chiba's prefectural government said a tornado hit part of Ichihara and destroyed a house.

Local officials said a man in his 50s was found dead in an overturned car near the destroyed house, as the tornado likely caused his vehicle to roll over.

At least 50 people were injured in the prefecture and elsewhere in the country, according to a Kyodo News tally based on information provided by rescuers and other authorities.

Central Japan prefectures, such as Mie and Shizuoka, and Kanagawa southwest of Tokyo have issued evacuation advisories to many of their municipalities. The Tokyo metropolitan government advised residents mainly in its western suburbs to evacuate.

As of 6 p.m., the typhoon had an atmospheric pressure of 955 hectopascals at its center and was packing winds of up to 216 kilometers per hour. The agency downgraded Typhoon Hagibis' intensity to "powerful" from "very powerful" around 6 p.m.

It is forecast to bring winds of 216 kph to the Tokai region in central Japan and the Kanto-Koshin region, including the Tokyo metropolitan area, and could potentially knock down houses, the agency had warned.

Tokyo Electric Power Company Holdings Inc. said as many as 770,000 homes were without power at one time in Chiba Prefecture.

Up to 1,000 millimeters of rain was expected in the Tokai region, and 600 mm in the Kanto-Koshin region, in the 24-hour period through midnight Saturday, the agency said.

Tokyo's Haneda airport, as well as Narita airport near the capital, were shut down.

There was no shinkansen bullet train service between Tokyo and Nagoya on Saturday. Just six early morning trains ran between Nagoya and Shin-Osaka, and operations between Shin-Osaka and Okayama were canceled from the afternoon.

Central Japan Railway Co. said train services on its Tokaido Shinkansen Line, departing from or arriving at Tokyo, are likely to be suspended on Sunday morning.

Meanwhile, West Japan Railway Co. said it is aiming to resume bullet train services between Shin-Osaka and Hakata on Sunday.

East Japan Railway Co. said it gradually suspended train runs in the Tokyo metropolitan area from Saturday morning and halted services around 1 p.m., including its Tohoku and Hokuriku shinkansen services.

Many stores in and around Tokyo were closed, or shelves were empty as people stocked up on food, water and other necessities.

Among manufacturers, Toyota Motor Corp. and Honda Motor Co. suspended operations at some of their plants Saturday.

According to the weather agency, the predicted rainfall amounts would be in line with those deposited by Typhoon Ida in September 1958, which left 1,200 people dead or missing across Japan.

That typhoon, known as Kanogawa in Japan, ripped through the Kanto region and the Izu Peninsula, causing the Kano River in Shizuoka Prefecture to overflow.