By Spain correspondent Miguel de Souza

Karim Benzema is set to spend the night in French police custody after being questioned in a blackmail case about a sex tape involving his French colleague Mathieu Valbuena.

The Real Madrid striker turned up at a police station in Versailles in order to “clear his name” after being place under formal criminal investigation by prosecutors.

It is claimed that Valbuena, the 31-year-old Lyon midfielder, was asked for money in return for the sextape not being published.

Three other men were placed under formal investigation after Valbuena was contacted by someone claiming to have the tape.

“When his name was mentioned by the press, Karim Benzema immediately let the investigating judge know he was available to investigators,” lawyer Sylvain Cormier Le Parisien newspaper.

A friend of the striker, who was targeted by Arsenal during the summer, was quoted as saying there was no way he would be placed under formal investigation.

Another former footballer, Djibril Cisse, was detained briefly last month but was later released without charge.

According to reports in France, Benzema mentioned the video to Valbuena during a national team training session at Clairefontaine in early October.

It was unclear whether he was offering friendly advice or trying to press his team-mate to pay the blackmailers.

Sources told French media that one of Benzema’s relatives was contacted by the blackmailers, who attempted to involve the player in their scheme.

French TV channel M6 reported that a close friend of Benzema’s brother was also taken into police custody on Wednesday.