MADRID, June 18 (Xinhua) -- The brother-in-law of Spain's King Felipe VI started serving a nearly six-year sentence for fraud and tax evasion, local media reported on Monday.

Inaki Urdangarin, who lived in Geneva and had been found guilty of embezzling millions of euros, landed in Madrid on Sunday evening, after a court in Palma de Mallorca on June 13 gave him five days to report to the Brieva prison authorities.

He entered the prison in the central province of Avila Monday morning.

Urdangarin, a former Olympic handball player married to the king's sister, Cristina, was found guilty of offenses against the public treasury, influence peddling, fraud and perversion of justice in the so-called "Noos case."

The Noos Institute, a non-profit that organizes sports events, overcharged for its services and billed for events that did not take place.

The money was diverted to private accounts via another company, Aizoon, where Cristina was on the board of directors. She was fined 136,950 euros (159,040 U.S. dollars).

A court ruled last year that Urdangarin had embezzled 6.2 million euros (7.2 million dollars).

Both he and Cristina were stripped of their royal titles after the court verdict.