On the evening of 17 December 1991, Belgian teenager Katrien De Cuyper (Dutch pronunciation: [kɑˈtrin də ˈkœypər]) disappeared in Antwerp.

In 2006, a 35-year-old man from Kessel, who had written to a magazine saying that he was with her on the night she disappeared, was arrested and charged with her kidnapping and murder; he was released four months later due to a lack of evidence.

On Tuesday, 17 December 1991, Katrien De Cuyper, a fifteen-year-old girl from Brasschaat, went to visit a friend in Lange Lobroekstraat in Antwerp.

[7] A month after De Cuyper's body was found, weekly magazine Blik received a letter from an anonymous sender claiming that they had given her a lift after she missed her bus the night she disappeared.

Police searching his house found child pornography on his computer and a box which contained newspaper clippings of articles about De Cuyper's disappearance and murder and copies of the letters sent to Blik and to her parents in 1992.