More than 1,000 young people are facing charges in Denmark after allegedly sharing two sexually explicit videos and a photograph involving underage subjects on Facebook Messenger. Danish police announced the charges on Monday morning, according to the Danish publication The Local.

The sharing occurred in late 2017 and depicted a sexual encounter between two 15-year-olds. The young people charged with sharing the materials ranged in age from 15 to the early 20s. When Facebook learned that the material was being shared, the company notified US authorities, who in turn alerted authorities in Denmark.

“We want to give out a warning to young people: think about what you’re doing," said Flemming Kjærside of Denmark's National Cyber Crime Center in a statement. "But they possibly do not know that it is illegal and that they can be convicted for distributing child pornography."

“We want to give out a warning to young people: think about what you’re doing,” Kjærside told Bloomberg. "Don’t ever share sex videos. It can have consequences for the victims and also for those distributing."

Most of the young people only shared the materials a few times. But some shared them more widely, according to authorities. About 800 of the people charged were male. If convicted, some of the young people could face prison time as well as restrictions from professions such as child care.