Former Birmingham City co-owner David Sullivan has hit out at Carsen Yeung.
The two regimes have been at war since Hong Kong tycoon Yeung first invested in 2007.
Grandtop International completed an £81.5m takeover last month with the promise of a massive cash investment in the squad.
But since then they have announced they are unhappy with managing director Karren Brady's contracted golden goodbye and discovered there were £6m worth of unpaid bills.
Sullivan told The Sun: "I'm livid, flabbergasted. We left a well-run football club. They seem to have a vendetta against us.
"You have to question what their motives are. We are told that they are going to spend £40m in January and they should be looking forward to that. Maybe they are now having a few doubts about spending it and see this as a possible excuse.
"We are fed up with all these stupid statements. They should get on with running their football club. If they want to waste police time it's up to them but we have nothing to hide. If Grandtop International haven't done proper due diligence that's up to them. This is sour grapes.
"Name me somebody who has bought a Premier League club and not found unpaid bills. There is always money owed on players.
"Then to hear talk about the fraud squad. I've never heard such a load of rubbish in my life."