The Refugee Action Coalition says a 16-year-old Lebanese refugee in Nauru has been treated in hospital after being attacked by a local armed man with an air rifle and then by two life guards.
Its spokesperson Ian Rintoul says the boy was attacked at a swimming spot near Anibare Lodge yesterday.
He says the local sprayed a few pellets at the direction of refugees, and when one of the pellets struck the Lebanese boy in the arm the shooter took off.
Mr Rintoul says the refugee appealed for the lifeguards on duty to help him.
He says the lifeguards admitted they knew the shooter but refused to help, call the police or agree to identify the shooter.
Mr Rintoul says the lifeguards then beat the refugee, leaving him with cuts, scratches and a badly injured knee that required hospital treatment.
There has been no comment from the Nauru authorities.