LETHBRIDGE, Alta. - Police in the Netherlands have arrested a man who is accused of sexually extorting a 14-year-old Lethbridge, Alta., boy online.

Investigators in Alberta say the accused met the boy through a social media platform and believed at first that he was speaking with a 14-year-old girl.

They allege the man later coerced the teen into sending sexually explicit photos, which progressed into threats and extortion for more pictures.

An investigation began when the youth went to police in April 2017.

Authorities in Alberta worked with their counterparts in the Netherlands and a 28-year-old man was arrested in Rotterdam on July 4 on charges that include possession of child pornography and threatening a minor to commit lewd acts.

Police in the Netherlands say that since then they have identified four other alleged victims.