MINAMISANRIKU, Japan - The first foreign leader to tour Japan's tsunami-ravaged coast, Australian Prime Minister Julia Gillard expressed shock and sorrow at the devastation and visited evacuees at a shelter Saturday, giving toy koalas and kangaroos to excited children.

Walking through a fishing village where hundreds of people are dead and missing, she said Minamisanriku looked as if it had been "bombed into oblivion."

Mayor Jin Sato showed her the red skeleton of the disaster management building where he was standing when the mammoth wave ripped off its shell March 11. Exterior stairwells were ripped from the walls. A small shrine of flowers had been created on a mound of rubble.

"It's a scene of incredible tragedy and incredible sorrow," Gillard said on the last day of a four-day trip here.

More than 27,000 people are dead or missing from the earthquake and tsunami. Tens of thousands are living in shelters after an estimated 90,000 homes were destroyed or damaged.

Recovery efforts have been complicated by the crisis at the Fukushima Dai-ichi nuclear power plant, where the tsunami wiped out power and cooling systems. Workers have struggled to stop radiation leaks, and the utility says bringing the plant fully under control may take all year.

Plant operator Tokyo Electric Power Co. said Saturday that 30 workers at the plant had exceeded the former limit of radiation exposure. That limit, 100 millisieverts a year, was raised amid the crisis to 250 millisieverts. None of the workers had yet reached that limit, the company said.

Leaks from the plant reactors have stabilized somewhat since the early days of the crisis, but some interior spaces in the quake- and tsunami-damaged buildings still have such high radiation levels the workers are not able to enter them.

A few hundred workers have toiled in rotating shifts at the plant since the disaster started, most of them middle-age men employed by TEPCO or affiliated companies. TEPCO spokesman Junichi Matsumoto said managers have been instructed to closely watch employees who are nearing radiation limits; measures that might be taken include moving workers from the riskiest tasks, such as clearing radioactive debris, to jobs indoors, such as clerical duties.

Workers in the U.S. nuclear industry are allowed an upper limit of 50 millisieverts per year. A typical individual might absorb 6 millisieverts a year from natural and manmade sources such as X-rays.

Radiation specialists say cumulative doses of 500 millisieverts have been shown to raise risks of future cancers. Evidence is less clear on smaller amounts, but in theory, any increased radiation exposure raises cancer risks.

Radiation sickness, which develops from acute exposure, sets in at 1,000 millisieverts. Symptoms include nausea, vomiting and hair loss.

The workers also face health problems due to fatigue and stress of working in the harsh environment, a doctor who spoke to them said this week. He said the workers have insomnia, dehydration and high blood pressure and are at risk of developing depression or heart trouble.

Meanwhile, Japan's railway company announced that bullet train service from Tokyo to the Sendai, the biggest city in the quake zone, would resume on Monday. Parts of the route had been restored earlier, but Monday is the first day the route is fully operational.