German prosecutors say they are investigating a man on suspicion of kidnapping, sexual abuse and possession of child pornography after police found a missing 12-year-old Swiss boy at his home.

Frankfurt prosecutors, who are in charge of cybercrime in Germany, said the man would be brought before a judge Monday afternoon.

The 35-year-old's identity was not released in line with German privacy rules.

Police on Sunday stormed the Duesseldorf home of the man and found the boy, who had been missing for over a week.

Swiss and German officials said the boy, who comes from Gunzgen in northern Switzerland, had met the man on the internet while playing online games.

The boy was reunited with his parents and examined by doctors.