TOKYO (AP) -– Criticism of the Japanese government's handling of the crisis at a radiation-spewing nuclear power plant has increased after an adviser quit in protest of what he lambasted as unsafe, slipshod measures.

Toshiso Kosako, a professor at the University of Tokyo's graduate school and an expert on radiation exposure, announced late Friday that he was stepping down as a government adviser.
Prime Minister Naoto Kan appointed Kosako after the magnitude-9.0 earthquake and tsunami that struck northeastern Japan on March 11. The disaster left 26,000 people dead or missing and damaged several reactors at the Fukushima Dai-ichi nuclear power plant — setting off the world's worst nuclear disaster since Chernobyl.
In a tearful news conference, Kosako said he could not stay and allow the government to set what he called improper radiation limits of 20 millisieverts an hour for elementary schools in areas near the plant.
""I cannot allow this as a scholar,"" he said. ""I feel the government response has been merely to bide time.""
Kosako also criticized the government as lacking in transparency in disclosing monitoring of radiation levels around the plant, and as improperly raising the limit of radiation exposure levels for workers at Fukushima Dai-ichi, according to Kyodo News agency.
The prime minister defended the government's response as proper.
""We welcome different views among our advisers,"" Kan told parliament Saturday in response to an opposition legislator's questions.
A government advisory position is highly respected in Japan, and it is extremely rare for an academic to resign in protest of a government position.
The science and education ministry has repeatedly defended the 20-millisievert limit as safe, saying that efforts are under way to bring the limit down to 1 millisievert. Some people have expressed concerns, noting that children are more vulnerable to radiation than adults.
Japan, which has 54 nuclear reactors, has long been a major proponent of atomic power, constantly billing its technology as top-rate and super-safe. Japan's government has also been trying to make deals to build nuclear power plants in other countries, although such attempts are likely to fall flat after the Fukushima Dai-ichi accident.
As the only country in the world to suffer an atomic bombing, as it did at Hiroshima and Nagasaki during World War II, Japan has long had a powerful anti-nuclear movement, and such protests have become louder recently.
Yoshiko Nakamura, a 50-year-old part-time worker, was among 450 protesters who gathered Saturday in Tokyo's Yoyogi Park. The demonstrators beat drums, shouted ""No more nukes"" and held banners that read ""Electricity in Tokyo, sacrifice in Fukushima.""
""We knew all along nuclear power was dangerous. I just didn't know how to express myself,"" said Nakamura, taking part in her second demonstration in two weeks. ""This is a great opportunity to send a message and voice my fears.""
Such demonstrations have become more frequent, including during the Golden Week holidays, which continue through the weekend and next week.
""What I had feared might happen has become reality,"" said Kenji Kitamura, a 48-year-old office worker. ""It is outrageous children are being exposed to such high levels of radiation.""