America's tax collectors want $702 million (£468 million) from Michael Jackson's estate.

Officials at the Internal Revenue Service (Irs) claim the pop music legend's estate owes them the money in unpaid federal taxes and penalties, and they've accused the administrators of undervaluing some of the star's assets by hundreds of millions of dollars.

The estate bosses previously challenged an Irs tax claim against the King of Pop's fortune in July (13).

A 2009 tax filing previously stated the Jackson estate had a $7 million (£4.6 million) taxable value, but in May (13), Irs bosses issued the estate a tax deficiency notice for $505.1 million (£337 million) in taxes and $196.9 million (£131.2 million) in penalties, according to Tax Court documents obtained by Reuters.

A Jackson estate spokesman claims the Irs's appraisal values are "based on speculative and erroneous assumptions unsupported by the facts or law," adding on Friday (23Aug13) the administrators have paid $100 million (£66.7 million) in taxes out of the estate's coffers.

Jackson died from an overdose of anaesthetic Propofol in 2009. His estate's beneficiaries are his three children, Prince Michael, Paris and Blanket, his mother Katherine and various charities.