The SuedDeutsche Zeitung has reported (via Google translate):
The tax office in Neukölln has confiscated the stocks and balances of Chinese traders on Amazon.de and blocked their merchant accounts on the platform. Earlier, Amazon Germany had contacted the relevant dealers and suggested that the German tax authorities could act against VAT fraud, reported Chinese media. The report apparently caused panic among Chinese traders. It should come to mutual denunciations, so the tax affair could draw more circles.
This action was, of course, part of the ongoing problem of tackling VAT fraud through online trading platforms that costs the UK well over £1 billion a year in lost VAT but which it was amazingly reluctant to tackle. In Germany it is estimated that 90% of Chinese traders do not have a valid VAT number.
The German tax authorities have taken appropriate action: this trade simply needs to be stopped.
Why have HMRC never been willing to do the same?