Six months after radiation leaks from the nuclear plant led to their evacuation, residents of nearby towns briefly return

Takashige Kowata thought he was prepared for the worst when he opened the door to his house for the first time in six months. But the trauma of seeing his family home abandoned amid the panic of a nuclear meltdown was compounded when he noticed a broken bathroom window.

"It looks like we have been burgled," the 63-year-old says, still too shaken to establish what is missing. "I can't believe that someone is capable of stealing from the victims of a disaster."

The intruders would have committed their crime with ease: Kowata's spacious house and garden lie about a mile from the scene of the Fukushima Daiichi nuclear disaster, which has turned large swaths of nearby land into an official no-go zone.

He was one of 80,000 people living within a 12-mile (20km) radius of the nuclear plant who were told to evacuate by the government in the hours after a magnitude 9.0 earthquake launched a tsunami that crashed through its protective seawall and triggered meltdown in three of its six reactors.

Kowata and more than 200 of his neighbours have been allowed to make a brief visit home to collect as many belongings as they can carry. It is a homecoming that many accept is likely to be their last.

Dressed in protective suits, masks and goggles, they have been given just two hours to survey the damage to the houses they have been barred from entering since the triple disaster struck north-east Japan on the afternoon of 11 March.

Months of radiation leaks from Fukushima Daiichi have rendered Okuma and the nearby town of Futaba uninhabitable for years, perhaps decades.

According to a recent government report, the annual cumulative radiation dose in one district of Okuma is estimated at 508.1 millisieverts, more than 500 times the acceptable yearly level and, experts believe, high enough to increase the risk of cancer.

"We've been told that we can't return home because of the radiation," says Kinuko Yamada, a 53-year-old woman who is making the trip with her husband. "I hope we can go back, but it could be 20 to 30 years before that happens. I'll probably be dead by then."

Radiation levels in the town are so high that decontamination could take years, or not succeed at all. Residents have so far been allowed just this one brief visit, organised by the plant's operator, Tokyo Electric Power [Tepco] and nuclear safety officials. The Guardian was the only foreign media permitted to accompany them.

Evidence of the area's dismal place in the history of Japan's nuclear power industry becomes visible soon after the convoy of buses passes through the police checkpoint.

All traces of ordinary life have been cast in eerie suspension: roadsides are overgrown with grass and weeds; shops and restaurants lie empty, and grand farmhouses – evacuated in the hours following the accident, when Tepco officials were considering abandoning the plant – stand quiet and deserted. Toppled walls and scattered roof tiles are reminders of the staggering force of the quake that caused the world's worst nuclear crisis since Chernobyl.

The only sound is the chirping of late-summer cicadas and the occasional beep of a Geiger counter. A scrawny black dog wanders into the road, sizes up his human visitors and scampers back into the woods.

And just visible above a line of trees is the roof of one of Fukushima Daiichi's reactor buildings. As our bus drives past, radiation levels inside surge to 61 microsieverts an hour (compared to the typical Japanese average of 0.34 microsieverts).Elsewhere inside the exclusion zone, at least 1,000 cattle are roaming wild after escaping from their farm homesteads, according to local authorities. Most pets, and tens of thousands of cows, pigs and chickens have starved to death.

A few days after residents returned to their homes, police officers and firefighters resumed the search for almost 200 tsunami victims in the area still listed as missing.

Some residents are reluctant to openly criticise Tepco, a major local employer. "I never worried about the nuclear plant before the tsunami," says one of Kowata's neighbours, a woman in her 60s who declines to give her name.

"When we left on 11 March we thought we would be back in a week or 10 days. Then the reactor buildings started exploding and we were more cautious, but even so I never thought it would be as bad as this. The power plant put food on the table around here ... I can't find the words to describe how I feel.

"I'm going to take back some valuables and our ancestors' spirit tablets – my parents are both dead. The earthquake left our family Buddhist altar in pieces, so I brought some flowers to place in front of it."

Her garden, usually a blaze of colour at this time of year, is a tangle of weeds and wild grass. "I spotted a few flowers blooming among the grass," she says. "I love flowers and told them I was sorry for not being able to look after them properly."

Inside, the doors have come away from their hinges and the walls have been pushed up by the force of the quake. "It's terrible," she says. "The kind of shock from which you can never recover. I want to come back, but it might be better for my peace of mind to stop hoping."

However, Kowata, a former local government official who witnessed the arrival of MOX (mixed oxide) nuclear fuel at Fukushima Daiichi last year, makes no attempt to hide his bitterness towards Tepco.

He has lived in this neighbourhood all his life and had only just built a new house, which he shared with four other members of his family. His father, like many other elderly tsunami survivors, died soon after being evacuated.

"I don't know how much Tepco and the government will give us as compensation, and in any case it will take a long time to arrive," says Kowata, who is living in rented accommodation in Aizu-Wakamatsu, a town farther inland.

"We can't wait around for them to take action. The nuclear accident is a man-made disaster.

"The government and Tepco kept telling us that this kind of thing could not possibly happen. Tepco hasn't changed when it comes to covering up trouble."

Just two hours after they arrived, Okuma's residents must board buses to take them back outside the exclusion zone to be screened for radiation.

They emerge from their homes gripping plastic bags bulging with clothes, valuables, heirlooms, children's toys and photo albums.

Kowata gathers his belongings, walks out of his front door and turns the key one last time. "As far as I am concerned, this is the last time I will see my home," he says. "The house itself isn't very old ... it's a great shame."

Halfway down the driveway he turns and fixes his gaze on the home he is leaving behind.

"I wanted to say thank you one last time. Now it's time to move on."