Prosecutors have accused a Dutch man of abusing around 400 boys and girls aged 12-14 he met in online chat rooms, coercing them into committing sexual acts via webcam. Victims have so far been identified in the Netherlands, the U.S., Belgium and Spain.

Prosecution spokesman Evert Boerstra said the suspect was arrested in July but prosecutors only revealed the scale of his alleged crimes at his trial Friday. Under Dutch law, he has not yet entered a plea, and is identified only as "Michel S."

A string of child abuse cases have horrified the Netherlands in recent years, including the 2012 conviction of Latvian-born Dutchman Roberts Mikelsons for physically abusing 67 children, including infants. Mikelsons filmed and distributed his acts, leading to 83 additional child pornography arrests around the globe.