Luckin Coffee announced on Thursday that it had about 2.2 billion yuan ($310 million) in fabricated transactions.

The aggregated sales amount associated with the fabricated transactions was from the second quarter to the fourth quarter of 2019, according to an internal investigation.

The figure has not been independently verified and is subject to change as the internal investigation proceeds.

Certain costs and expenses were also substantially inflated by fabricated transactions during this period, the announcement said.

The shares of Luckin collapsed as much as 81 percent, the most within one day since its IPO last May.