Over the course of a "strange" and "tragic" 60 minutes, a Queensland woman's father drowned and her partner was shot in the head on the mid north coast, police say.
The two events were not linked, but just happened by chance within an hour of each other near Coffs Harbour on Wednesday afternoon, police said.
Emergency services were called to Woolgoolga Beach about 4.30pm on Wednesday, where the body of a 57-year-old man was found at the water's edge.
An hour later police were called to Darkum Road, Mullaway, six kilometres from the beach, after a 32-year-old man was shot in the right side of the head.
Police arrested a 20-year-old man at a Woolgoolga home about 11.30am on Thursday, and he is being questioned by police over the shooting.
Coffs-Clarence Commander, Superintendent Mark Holahan, said as police investigated the two events, they realised the drowning victim was the father of the shooting victim's girlfriend.
"There are no links between the two separate events. It would just appear to be a tragic set of circumstances for that family," Superintendent Holahan said.
"It's just a strange set of circumstances."
Superintendent Holahan said the shooting victim and his partner, who live in Queensland, had been at the beach when the body was found.
"They'd gone and visited some friends in Coffs Harbour for the day ... and took the opportunity to stop at the beach."
But Superintendent Holahan was not able to confirm earlier reports the family got into a fight with a bystander at the beach, who followed them to the Mullaway house and shot the 32-year-old man in the head.
Police believe they did see each other earlier that day.
"We honestly believe [the shooting] is as a result of a personal matter from some years ago."
"Their paths have crossed yesterday. We believe once their paths crossed, the second vehicle followed the victim and that altercation took place.
Superintendent Holahan said the circumstances of the shooting would become clearer once they had interviewed the alleged gunman.
"It's an unfortunate thing.
"I've been a policeman for a little while and while you see some families go through some situations, I've never seen a family go through two situations back-to-back within a matter of hours."
Police said the drowning was not suspicious, and the shooting was not linked to bikie activity.
The shooting victim suffered facial wounds and was taken to Coffs Harbour hospital, where he was in a stable condition on Thursday afternoon.