A fish market in Ishinomaki, some 350 kilometres (220 miles) northeast of Tokyo, received a parcel containing gold bars weighing a total of two kilograms (4.4 pounds) in early February, about a month ahead of the disaster's second anniversary on March 11.

Kunio Sunow, president of the Ishinomaki Fish Market which was destroyed in the disaster, said he casually opened the mystery parcel addressed to him.

"I was stunned because... in there was 24-carat gold in two plates," he told AFP on Friday.

"We don't have to identify this person of goodwill... but we want to let them know we are grateful. If possible, I want to invite him or her to the completion of a new market" set for early 2015, he added.