Two Bonsai enthusiasts have launched an emotional plea to thieves who stole seven trees from them, offering care instructions for their "children".

Seiji Iimura and his wife Fuyumi said the prized miniature trees were taken from their garden in Saitama, near Tokyo.

"There are no words to describe how we feel," Mr Iimura wrote. "They were precious [to us]."

The tiny trees are worth at least 13m yen ($118,000, £91,750), CNN reports.

Stemming from East Asia and often associated with Japan, Bonsai is a delicate art-form based on specialist cultivation techniques.

The miniature plants are grown in containers. They require expert care and mimic the shape of fully-sized trees.

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One of the couple's stolen trees is a Shimpaku Juniper - one of the most sought-after Bonsai types among collectors and enthusiasts. It is said to be worth over 10m yen ($91,000; £70,720).

"The Shimpaku lived for 400 years, it needs care and can't survive a week without water," Mrs Iimura told CNN.

"It can live forever, even after we're gone. I want whoever took it to make sure that it's properly watered."

She confirmed to BBC News on Tuesday their trees were still missing.

"We are sad and forlorn but we will continue to protect our Bonsai" Mrs Iimura wrote on Facebook. "In the meantime, we will continue cultivating trees worthy of everyone's praise."

Fellow gardeners and bonsai collectors reached out to the Iimuras online to express their sympathy and solidarity.

"Unforgiveable," one commented on her post. "These thieves do not know what it means to steal a bonsai, let alone seven. All the tender loving care goes with the theft."

"Bonsais are meant to be revered and celebrated and should be beyond human greed. I am heartbroken to read this," wrote another.