Police have released a face-fit image of a man they believe to be linked to two alleged assaults in Theodore.

Police allege a woman was grabbed from behind during an attempted sexual assault while running in Tuggeranong Hill Nature Reserve in March.

In an earlier incident in February, the man allegedly approached and physically interacted with a child near the Theodore playing fields.

Police say DNA analysis has linked the same man to both incidents.

He is described as Caucasian in appearance, tall and slender, with brown curly hair and a beard.

Anyone who can identify the man should contact police via the Crime Stoppers website.