COPENHAGEN — About 1,000 adults and adolescents may face prosecution for sharing online video of two 15-year-olds having sex, and more people may be charged for spreading the images, the Danish National Police said Monday.

Consensual sex between 15-year-olds is legal in Denmark, but anyone who forwarded the video violated the law against distributing child pornography, the police explained. The two video clips — one 50 seconds long, the other 9 seconds — were shared through Facebook’s Messenger app.

The case prompted outrage when it was first reported last year, because the video appeared to show the girl being abused, penetrated with foreign objects. The girl has said that she consented to sex, but not to the abuse or to the recording.

The police notified 1,004 people on Monday that they faced preliminary charges, which the police can issue on their own; prosecutors will decide whether to proceed with charges and take the cases to trial. Investigators are looking into whether the video was distributed on platforms other than Facebook.