A Cook Islands Police Service spokesman says the incident took place in Nikao at around 10:30am.
The police say the man suffered “serious injuries”, including a spinal injury. He was rushed to Rarotonga Hospital, where the police interviewed him. They arrested the suspected offender yesterday.
The arrested man is also believed to be a Fijian national.
Police say he will face charges relating to the assault of the male as well as a charge of male assaults female.