Zhongzhi Enterprise Group (ZEG) has an asset management arm that at its peak reportedly handled more than a trillion yuan ($139bn; £110bn).

Authorities said they are investigating “suspected illegal crimes” against the firm, in a statement on the weekend.

This comes days after reports that ZEG had declared it was insolvent.

The struggling firm reportedly told investors in a letter last week that its liabilities - up to $64bn - had outstripped its assets, now estimated at about $38bn.