Nuclear Regulation Authority Chairman Shunichi Tanaka vowed Thursday to ensure that the Fukushima No. 1 nuclear plant is made safe as the regulatory body marked the first anniversary of its launch.

"The situation at the Fukushima No. 1 plant remains unstable. Every time a radioactive water leakage, a blackout or other trouble occurs, I think of the people, living inconvenient lives in areas where they have been evacuated, getting worried about their hometowns," Tanaka, a native of the city of Fukushima, said in a statement.

"We will do our utmost, with a strong belief that we can and must overcome this issue," he said.

Approximately 150,000 people from Fukushima Prefecture still live as evacuees more than two years since the start of the world's worst nuclear crisis since the 1986 Chernobyl disaster.

The NRA was established on Sept. 19 last year with the government hoping to restore shattered public confidence in nuclear regulation following the Fukushima crisis.

One of the agency's key features is the greater independence it has been given.

Its predecessor, the Nuclear and Industrial Safety Agency, lacked teeth as it was a part of the Ministry of Economy, Trade and Industry, which is tasked with promoting nuclear power.

Tanaka described the past year as "groping in the dark" but said he is seeing progress toward the goal of creating a culture of nuclear safety.

"We have made efforts to be transparent, neutral and to make judgments from scientific and technical perspectives. As a result, changes are definitely occurring, although gradually," he said.

In addition to overseeing the situation at Fukushima No. 1 and measures taken by Tokyo Electric Power Co., the NRA has to assess the safety of other reactors that have been left idle.