SUNBURY police are investigating an increase in hoax calls to emergency services in Sunbury and the Macedon Ranges.
Police said there had been 20 hoax calls in the past 12 months.
"That's a lot more calls than usual," Senior Constable Jacqui Newman said.
"The callers say there are fires and accidents which police, the CFA and other emergency service units have to attend.
"We are investigating the calls but at this stage have no suspects in the cases."
Senior Constable Newman said police weren't sure if the same person was responsible for all the calls.
Sunbury CFA station officer Tony Ford said it had attended a number of hoax callouts recently, including one to a car fire on the Melbourne-Lancefield Road last Wednesday afternoon.
Senior Constable Newman said police also attended a call to a non-existent accident on the Calder Freeway two weeks ago.
She said school holidays sometimes resulted in more calls than usual, but she was unsure if the most recent calls fitted into that category.
"These calls are time-wasters. There are more important things these resources are needed for, but instead we are going to where people supposedly need help."
She said anyone found guilty of making hoax calls faced a maximum fine of $9000.
A CFA spokesman said: "It would be disappointing if someone was making hoax calls, seeing as many of the people attending them are volunteers and they are giving up their valuable time."
Information to Crime Stoppers 1800333000.