The storm -- which downed power lines, flipped vehicles, altered work schedules and stopped train service around Tokyo -- was headed for the tsunami-devastated northeastern region, Kyodo News service reported. Heavy rains caused by the typhoon prompted officials in much of Japan to warn of the danger of mudslides.
Roke made landfall in Hamamatsu in Shizuoka prefecture Wednesday and then began moving up Japan's Honshu island, The Wall Street Journal said.
Tokyo Electric Power Co. said it took precautionary measures at its damaged Fukushima Daiichi nuclear power facility to minimize the spread of radioactive materials by strong winds.
Officials blamed typhoon-triggered landslides and flooding for the deaths of at least six people, Kyodo News said. At least four people were reported missing.
About 7,800 people across the country were told to evacuate, while another 1.21 million people were urged to evacuate voluntarily, Kyodo News reported.
The storm knocked out power to more than 460,000 households in Tokyo Electric's operating area and slightly more than a quarter-million households in Chubu Electric Power Co.'s service area, the Journal said.
About 40 train lines operated by East Japan Railway Co., including bullet-train routes, were stopped, the Journal said. At least 300 domestic airline flights were canceled.
Toyota Motor Corp. temporarily halted operations at 11 of its factories Wednesday, while Honda Motor Co. altered its hours so workers wouldn't have to travel when the typhoon was expected to peak.