A call was made from a public phone at Tikitapu about 2pm yesterday. The caller, who sounded like a child aged between 10-14, said someone had drowned at the waka ama regatta at the popular lake near Rotorua.
Sergeant Chris McLeod said about seven police officers and St John ambulance staff rushed to the lake. Rotorua Coastguard also started preparing.
However, when they got to Tikitapu, no one knew anything about the accident, Mr McLeod said.
Officers asked several people before heading to all other lakes in the area, on the off-chance the caller had the location wrong.
He said police officers spent about an hour checking popular swimming areas at Lake Okareka and Lake Tawera, asking anyone they could find if they knew any thing about a drowning.
"It took us away from trying to catch burglars and people stealing from cars, not to mention keeping people on our highways safe, which was a real concern at the weekend with all the fatal crashes in the North Island.''
Mr McLeod said once all the options had been exhausted, emergency services were stood down and they turned to finding who was responsible for the call.
"As far as we know, it was a young person playing on the public phone outside the Blue Lake Holiday Park.''
Mr McLeod said the callout was infuriating as they believed they had a real serious situation.
"We put a number of people at risk _ police officers, search and rescue, St John people.
"They have all had to travel at speed to the location to minimise any risk of a possible drowning.''