Several yachts have capsized during a regatta in north Otago, with an unknown number of people ending up in the water.
A police spokeswoman said emergency services were called at 12.05pm to Lake Aviemore with a report several yachts had capsized amid high winds. Coastguard, police and ambulance were attending.
One person was being checked for potential hypothermia, she said. As of 1.35pm everyone was out of the water - it was not clear how many people had fallen in.
A St John Ambulance spokeswoman said two vehicles attended the incident and 16 people were assessed.
Of those 11 had minor injuries, five were not injured.
No one was transported by ambulance.
A Coastguard boat was attending the regatta, a spokesman said.
He did not have more information on what had happened.
The Aviemore Classic race runs the length of Lake Aviemore, between the Otematata River and Aviemore Dam. The race is run by the Timaru Yacht and Cruising Club.
Timaru Yacht and Power Boat Club trailer boat section spokesman Steve Hutton said the capsized yachts are now being towed to safety.
Russell Phillips, administrator of a Southern Tack event which is also being held on Lake Aviemore this weekend, said it was not unusual for boats to capsize.
"We have a lot of safety craft there," he said.
"I'm disappointed to hear there have been some capsizes but it's not unusual."