Police in Germany are appealing for help in tracing a young girl after she was seen being abused in child pornography videos found on the 'dark net'.

National investigators from the Federal Criminal Police Office (BKA) have joined the Central Office for Combating Internet Crime (ZIT) and the Prosecutors Office of Frankfurt am Main in searching for the child, who is between four and five years old.

Police said the videos and images of the girl being abused were first discovered in July. They believe the exploitation began in October last year.

National investigators from the Federal Criminal Police Office (BKA) have joined a cyber crime unit in searching for the child (pictured), who is between four and five years old

Police said the videos and images of the girl being abused were first discovered in July and assume the exploitation had begun in October last year

They believe the ordeal could be ongoing because the child is thought to still be held by her abuser.

BKA investigators said that despite an extensive search, they have not identified a suspect in the case.

Because they have exhausted all leads, they have released her images in a desperate attempt to find her.

Because they have exhausted all leads, they have released her images in a desperate attempt to find her

She is described as having blonde - or dark blonde - hair and with brown eyes.

The girl speaks German and is described as having a slim build.

Those with any information on the young girl are asked to get in touch with police through the BKA website.