YOKOSUKA NAVAL BASE, Japan — Why a dozen remote-controlled devices around Yokosuka went haywire last month remains a mystery, but the U.S. Navy and Japan’s government are not pointing fingers at military radio use.

Both groups question an Asahi Shimbun report that problems with garage and car doors may have been caused by the USS Kitty Hawk aircraft carrier. Asahi Shimbun pointed to the timing of the disturbances, which began when Kitty Hawk returned to Yokosuka Naval Base on Sept. 15. The newspaper also reported that one of the signals the carrier uses for air-control communications is the same as the remote controls in question.

Japan’s Ministry of Internal Affairs and Communications confirmed that it received more than dozen complaints from people living in Yokosuka and south Yokohama around that time, said Toru Nakao, ministry radio policy division official. But the group has not identified any illegal radio signals, he said.

“We have not identified the cause and it is being investigated,” Nakao said.Also, signals used for remote-control devices are weak. Japanese laws governing radio broadcasting do not require authorization for such devices, he said, adding that the ministry has not queried U.S. forces.

The 7th Fleet is aware of the reported disturbances and is reviewing them, according to a 7th Fleet statement. There is no evidence the signal came from the ships, according to the statement, but there are indications it may have come from commercial sources. The Navy uses only frequencies authorized by the Japanese government, according to the statement.