Prosecutors are coming down hard on Yang Yin, a Chinese national and former tour guide living in Singapore, in a case that has rocked the island city-state. An 89-year old Singaporean woman allegedly entrusted him with purchasing a $371,000 ($500,000 SGD) painting by internationally-recognized Chinese artist Xu Beihong. Instead, prosecutors say that he duped the elderly woman with a replica of the work.

Details have been emerging from a criminal trial against Yang that has been moving in fits and starts, according to reports in Channel News Asia and Straits Times.

In a court session earlier this month, Yang had said he was not fit to be cross-examined by prosecutors, at which point the deputy presiding judge of the state courts, Jennifer Marie, adjourned proceedings so that he could undergo a check-up at a nearby medical center. Now, the trial is back on.

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Yang is charged with misappropriating funds from Chung Khin Chun, totaling about $817,000 ($1.1 million SGD) between 2010 and 2012, according to reports. Yang reportedly initially claimed that $371,000 was used to buy a painting by Xu Beihong, titled Horse Drinking Water, that the widow had instructed him to purchase.

However, he later changed his story and said the $371,000 was a gift that he had used to pay off family medical debts. Deputy public prosecutor Sanjiv Vaswani told Channel News Asia this story was a “fabrication,” though exactly what part is not entirely clear. Did Yang purchase a “replica” of the work or simply abscond with the funds?

Evidence in Yang Yin’s court case.

The work in question is an unframed ink and color painting on paper with multiple crease marks, depicting a horse drinking water. The artist is known for his focus on horses, and his works have sold for millions at auction. In 2015, for instance, Horses Drinking, a 1934 ink and color on scroll work, sold for $3 million at Christie’s.

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The prosecution referenced a receipt found among Yang’s possessions in the house he had lived in with Chung. It was dated March 1, 2010, for the amount of $371,000. Yang reportedly maintained that he had never seen the paper before and did not recognize it.

Vaswani reportedly raised the notion that Yang had obtained the receipt to deceive the widow—who is suffering from dementia—into believing he had bought the painting with the money she gave him.

In late May, Yang pleaded guilty to a total of 120 charges, including falsifying receipts made to his company, as well as for immigration offenses.

artnet News reached out to Vaswani as well as Yang’s attorney, Wee Pan Lee, for comment but did not receive an immediate response.