New Delhi (CNN Business) Walmart's big bet on India has suffered another major setback.

The head of Flipkart, the Indian online retailer Walmart bought in May, stepped down on Tuesday following an independent investigation into allegations of "serious personal misconduct."

Binny Bansal, co-founder and CEO of Flipkart, resigned after the investigation by a global law firm revealed "lapses of judgement," Walmart said.

But six months in, the deal has lost some of its gloss. Walmart told investors in October that the Flipkart purchase would shave about $740 million off its quarterly profit.

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