A 17-year-old boy was taken to hospital and required dental care after an assault at Canford Cliffs beach.
The victim was punched in the face several times by another male teenager who had been arguing with oine of his friends.
The victim was then taken to hospital for treatment to facial injuries and also required dental treatment after having a tooth knocked out and another chipped.
The incident happened at around 10pm on Friday, April 29 on the promenade at Canford Cliffs beach.
Police are appealing for witnesses or anybody with information to come forward.
Police Constable Jenny Walsh, of Poole police, said: “This assault left the victim with nasty injuries and we have been carrying out a number of enquiries into this matter.
“I appreciate the incident was some time ago, but we have now been able to obtain further details from the victim and I would urge anyone who witnessed what happened, or has any information that might assist our enquiries, to please contact us.”
Anyone with information is asked to contact Dorset Police at www.dorset.police.uk/contact, via email firstname.lastname@example.org or by calling 101, quoting occurrence number 55220067964.
Alternatively, independent charity Crimestoppers can be contacted anonymously online at Crimestoppers-uk.org or by calling Freephone 0800 555 111.