According to Luxembourg financial regulator CSSF, its Spanish equivalent, the Comisión Nacional del Mercado de Valores (CNMV), had suspended the financial instrument from trading the same day.

No reason was given for the suspension of the chain, in which Chinese conglomerate HNA group holds a 30% stake. HNA is known to be trying to sell off assets to reduce its debts.

On Tuesday, Bloomberg reported that HNA’s efforts to sell off its stake had resulted in interest from other funds and companies in the industry, such as Elliott Management Corp and Apollo Global Management.

In January, the Financial Times reported that the group had had its bank accounts temporarily frozen. In April, the Financial Times reported that the group’s debts had soared to $94bn.

HNA executives said in January that its liquidity woes were temporary. While in March it told the Financial Times that it had a “healthy mix of cash flows” and did not expect any further disruptions going forward.

According to the Financial Times, HNA group started out as an airline on the island of Hainan. Today the finance-to-aviation conglomerate has almost a 10% stake in Deutsche Bank and owns a 82.5% stake in Frankfurt-Hahn airport in Germany.