MUMBAI: The Enforcement Directorate ED ) recently attached a flat owned by Nirav Modi 's sister Purvi Modi in central London. The property worth around Rs 72 crore is believed to have been bought last year with money that Modi obtained from Punjab National Bank PNB ) through forged letters of undertaking (LoUs).It is the first foreign attachment in the Nirav Modi case.The ED, which got a court order to provisionally attach the property, is sending it along with a letter of request (LR) to UK authorities for its implementation. A source said, "The UK Proceeds of Crime Act authorises them to attach the property in their country related to the crime committed in India on request."Nirav allegedly defrauded PNB of Rs 6,500 crore through fraudulent LoUs. Of this, he had diverted Rs 890 crore into the account of a company controlled by Purvi and her husband Maiank Mehta through shell companies.In one such transaction, the PNB money was sent to Modi-controlled shell companies in Dubai and Hong Kong. From there it was diverted into the account of a company controlled by Purvi, Fine Classic FZE. This company diverted Rs 70 crore into the account of another shell company-Belvedere Holding in Singapore- also controlled by Purvi.Modi's chartered accountant, Raghuraman Iyer had helped Purvi form Belvedere Holding along with a trust, Monte Cristo, in New Zealand. Purvi used Belvedere Holding money to purchase the London flat.Sources say Purvi is the third most important person in the bank scam after Nirav and his aide Mihir Bhansali, who is believed to be in the US. Officials say although Purvi was not directly handling the shell companies, the fact that her name was frequently used in suspicious companies indicates that she had a major role to play in the money laundering.