(Yicai Global) June 15 -- Chinese regulators have wrapped up their on-site investigation of the curious case of Nasdaq-listed Luckin Coffee's falsification of financial data, and their report on it now awaits a reply from higher-ups, Yicai Global learned from an insider.

The investigation was led largely by the Ministry of Finance's Supervision and Evaluation Bureau, the insider said.

Luckin sought to pin the financial fraud on its ex-Chief Operating Officer Liu Jian in April when it first came clean, but the real story is starting to look more sinister. The bulk of internal emails London-based audit firm Ernst & Young secured in the on-site investigation it opened at this year's start proved that higher-level executives could not have been unaware of such acts, Yicai Global learned.

This may explain why Jenny Qian, Xiamen-based Luckin's former chief executive ousted from her post last month now cannot be reached, as a source close to the coffee chain's management told Yicai Global.

The internal emails include content relating to payment applications for bogus transactions, preparation and arrangement of setup of affiliates and the effects of the fake deals, the source noted, adding Qian is the highest-ranking executive who reviewed and approved these emails.

Qian, also the spartanly furnished chain's former chairwoman, is the right hand of Charles Lu, and has followed in the wake of the car rental billionaire -- the coffee chain's actual controller -- for 13 years, public information shows. She vanished from public view after her removal in May over one month after the data falsification scandal broke.

Chinese regulators have their hands on e-mails indicating Lu guided this fabrication of financial indicators, Chinese media Caixin reported earlier this month. He will be charged and is highly likely to face criminal prosecution, per its report.

Luckin has been growing at a staggering pace since its 2017 inception. As of the end of last year, the startup, which opened its first store in China in October 2017, surpassed arch-rival Starbucks, which has done business in the Chinese market for 20 years, in the number of outlets in the country with 4,507.

It listed on the US Nasdaq market a mere 18 months after its advent on May 6 last year to great fanfare. One year on it is now in possession of a de-listing notice the bourse served on it on May 15.

Luckin also filed a confession with the US Securities and Exchange Commission in early April, admitting it falsified CNY2.2 billion (USD311 million) in transaction sums between last year's second to fourth quarters. Various US-based law firms have brought class action lawsuits against the company since then.

Editors: Tang Shihua, Ben Armour