(CNN) -- Hundreds of residents of an area contaminated by a catastrophic reactor meltdown at a nuclear plant in northeastern Japan have been allowed to return home three years after the disaster.
An evacuation order, declared in the aftermath of a devastating tsunami that crippled the Fukushima-Daiichi nuclear plant in March, 2011, was lifted at midnight on Monday from the Miyakoji district of Tamura city in Fukushima Prefecture.
Residents of the town, who have been in limbo ever since, are now free to re-inhabit their homes following decontamination work in the area.
The Tohoku earthquake and subsequent tsunami off Japan's northeastern coast led to the worst nuclear disaster since Chernobyl in 1986. Three reactors melted down, with the resulting radiation fallout forcing nearly 140,000 people from their homes.
Around 138,000 Fukushima residents remain in temporary accommodation, with a number of cities, towns and villages reduced to ghost towns due to continued high levels of radiation.
"We are doing as much as possible (to allow) the other residents can come home. We are strengthening support towards the residents (and) strengthening the decommissioning work," a TEPCO spokesperson told CNN.
Monday's lifting of the exclusion order is the first time an area this close to the site has been cleared. Miyakoji is 12 miles (20 kilometers) from the plant, on the edge of the initial exclusion zone.
Prior to the lifting of the order, some Fukushima residents were allowed to stay overnight in their homes, subject to registration. All restrictions on their movements have now been lifted within the cleared district.
355 residents -- out of a total 116 households -- are now free to return to their homes in Miyakoji permanently. The city of Tamura is one of eleven settlements in Fukushima that are still subject to evacuation orders.
However, concerns remain about background radiation levels and uncertainty surrounding the safety of the area, especially given past concerns about the reporting of radiation levels in the area by Fukushima's operator, Tokyo Electric Power Company (TEPCO). Last month, Miyakoji residents were told at a community meeting that radiation contamination levels had lowered sufficiently to enable their return to the area -- though some voiced concern over existing radiation levels despite decontamination efforts around some communities.
"Yes, I am a bit worried. But it's my land, my house, so I am feel safer and more at home here," one resident told broadcaster NHK.
Areas are declared suitable for habitation if residents are exposed to a maximum of 20 millisieverts of radiation per year. Officials have said they would like to get radiation exposure down to one millisievert a year.
The containment effort at the wrecked Fukushima plant has been beset by problems, with regular reports of leaks of contaminated material. Earlier this year, an estimated 100 metric tons of highly contaminated water flowed over a barrier around a containment tank and is being absorbed into the ground, TEPCO said in a statement -- though it denied there was any leakage into the nearby Pacific Ocean.