Murdered child’s photo used to promote daycare center

A photo of 4-year-old French boy Grégory Villemin, whose 1984 murder remains unsolved, was used to advertise a daycare center at the Montreux Jazz Festival, prompting the child's parents to file a lawsuit against the event's organizers.

The famous Swiss festival used Grégory's picture in its daily newsletter on Saturday, and the ad was later spotted and posted on the internet by a member of the public on Tuesday.

In a statement, the event's organizers apologized for what they called a "regrettable mistake" caused by a young graphic designer who used the photo of Grégory without knowing its significance. Some reports say it was an intern who chose the photo by typing "enfant" — or "child" — into Google images.

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Organizers said they would immediately withdraw all copies of Saturday's newsletter.

Grégory's parents, Christine and Jean-Marie Villemin, were "outraged" when they found out about the use of their son's photo. Their lawyer, Thierry Moser, said they are demanding the festival organizers issue an immediate and sincere letter of apology. If they do not, Moser has said he will take legal action on behalf of the Villemins to "punish such seriously inappropriate behavior."

Grégory Villemin was found dead in a river near his parents' home in the east of France with his hand and legs tied. His 1984 murder is one of the country's most notorious crimes.