The promising youngster agreed a move to the Barclays Premier League champions in a deal reported to cost as much as ?670,000.
But strict rules in Holland prevent children under the age of 16 dealing with agents, and Dan Kramp of the Forza Fides agency is alleged to have played a key role in the deal.
Investigation: Ake's move to Chelsea has sparked fury in Holland
According to the Sun, Kramp reportedly took Ake to Chelsea during the Christmas holidays with the defender, who turns 16 on Friday,? even bragging on his Twitter account about 'heading to London,' and staying at 'a good hotel'.
The deal has caused uproar in Holland, with Dutch Labour MP Tjaeerd Vekken raising the issue in parliament.
'The rules clearly state that agents can't do anything with children under 16,' Vekken said.
'Yet this agent turns up with a 15-year-old at Chelsea so the FA has got to tackle this issue.'
Treading on thin ice: Chelsea found themselves in hot water over the signing of Kakuta
A spokesman from the Dutch FA added: 'It's a transfer involving a player who is not yet 16 so our integrity unit is going to take a look at it.'
Chelsea denied any wrong doing over the Ake pursuit in December. A spokesman said: 'We've kept Feyenoord abreast of our interest from the very beginning and as a result have agreed terms with the club for the player's transfer to Chelsea in July.'
Having been at the centre of controversy with the Gael Kakuta scandal last year, Chelsea were thought to have made their approach for Ake as above board as possible, making regular contact with Feyenoord's sporting director Leo Beenhakker to ensure they were not accused of any misdemeanours.
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Source: Daily Mail
Source: Daily Mail