Takayuki Ueno, 43, who lost his parents, daughter and son in the March 11, 2011 tsunami, stands in front of his house that was damaged by the disaster in Minamisoma, Fukushima Prefecture, Japan, Feb 15, 2016. Survivors exposed themselves to high levels of radiation five years ago while searching for family members swept away by the tsunami that triggered meltdowns at Japan's Fukushima nuclear plant. The disaster in March 2011 killed nearly 16,000 people along Japan's northeastern coast and left more than 2,500 missing. Family members continue to look for the bodies of their missing loved ones, when access to the area is permitted, as they still try to bring closure to their loss.[Photo/Agencies]

OKUMA, Japan - Takayuki Ueno did not hesitate one moment to expose himself to high radiation five years ago while searching for family members swept away by the tsunami that triggered meltdowns at the Fukushima nuclear plant.

The bodies of his mother and daughter Erika were found. But Ueno braves radiation and bitter cold on beaches near the crippled plant to look for the remains of his father and son Kotaro, then three years old, to bring closure to his loss.

"My highest duty as a parent was to protect my children, which I failed to fulfill. That makes me the worst parent, and I have to apologise to them," Ueno, 43, said.