ZURICH • Fifa on Monday sacked deputy general secretary Markus Kattner for financial "breaches" involving secret bonuses worth millions of dollars, according to sources close to an inquiry by the world body.

His downfall topples another member of former president Sepp Blatter's inner circle at football's world body.

Kattner, a 45-year-old German-Swiss national, had been acting general secretary after previous general secretary Jerome Valcke was also dismissed for irregularities.

"Kattner has been dismissed from his position, effective immediately," the world body said in a statement. "Fifa's internal investigation uncovered breaches of his fiduciary responsibilities in connection with his employment contract."

A source close to an internal Fifa investigation said: "We are talking about significant sums of money, millions of dollars."

The source added that the money came from bonuses under a contract whose terms were kept secret from Fifa's audit committees.

The internal Fifa inquiry, carried out by the Quinn Emanuel law firm, "covers the period from 2008 to 2014", the source said.

According to another source familiar with the workings of Fifa, these bonuses would have been approved by the world body's financial committee, who decided how much the president, general secretary and deputy general secretary were paid.

The president of this committee was former Fifa finance chief Julio Grondona, an Argentinian and close Blatter ally. Grondona died aged 82 in 2014 and has been largely implicated in the Fifa scandal over the past year.

"Fifa will not comment further on any of the details, but will continue its cooperation with the relevant authorities," said the Fifa statement.

The Swiss justice ministry, meanwhile, said that "as of today, Mr M. Kattner is not under investigation" by prosecutors.

Swiss prosecutors are investigating Blatter - who is serving a six-year Fifa ban - and Valcke. The latter was sacked and suspended from football activities for 12 years after being linked to the sale of black market World Cup tickets.

Blatter is under investigation for making a "disloyal" payment of 2 million Swiss francs (S$2.78 million) to former Uefa boss Michel Platini, who has also been banned from football activities. Kattner, as finance director, signed off on the payment that Blatter ordered to be made to Platini in 2011.

The latest sacking is a new blow to Fifa's reputation as it seeks to redeem its scandal-tainted name under new president Gianni Infantino, who was elected in February.

Kattner's dismissal is a new sign that Fifa's past misdeeds have still not all been brought out into the open.

AGENCE FRANCE-PRESSE