Nagano Gov. Yasuo Tanaka on Tuesday imposed a smoking ban at nearly all of the prefecture's public facilities, the first blanket prohibition in Japan.

Tanaka implemented the ban at 2 p.m., one hour after announcing the measure at a news conference. He said he has asked the prefectural assembly to cooperate and expressed hope that boards of education will also ban smoking at public elementary and junior high schools.

According to the sanitation department, Nagano is the first prefecture in Japan to implement a complete ban on smoking at its facilities, including schools and police stations.

Saga and Yamaguchi prefectures have banned smoking in some facilities, including the prefectural government buildings.

A growing number of local governments are reinforcing antismoking measures after a health-promotion law took effect earlier this year. But it is rare for a ban to take effect without an adjustment period.

Smoking is now allowed only outside and on the rooftops of Nagano-run facilities, but Tanaka said he wants to prohibit smoking on all premises, including the outdoor and rooftop areas, in three months.

However, a handful of locations such as lodging facilities, hospitals, nursing homes and police interrogation rooms will be exempt under certain conditions.