A search for a possible vessel in distress was launched off the coast of Port Kennedy.
The Joint Rescue Coordination Centre in Canberra notified WA Police that an unregistered EPIRB had been activated around 8.05am on Monday.
Water Police and the RAC rescue helicopter were deployed.
It was later determined a vessel had accidentally activated its EPIRB.
Southern suburbs electrician claims $1.8 million Lotto win
A southern suburbs electrician has claimed a $1.8 million Lotto win.
Works continue on Pinjarra's Munday Avenue extension
Works are continuing on the $7 million Munday Avenue extension in Pinjarra.
Halls Head support worker charged with historic child sex offences
A 33-year-old Halls Head man who allegedly worked with children without holding a valid Working with Children Check has been charged with a series of historic child sex offences.
Severe thunderstorm warning cancelled for Mandurah, Bunbury
A severe thunderstorm warning has been cancelled for parts of the Lower West and South West including Mandurah and Bunbury.
Fortnightly red bin collections to remain in the City of Rockingham after council rejects motion
Fortnightly red bin collections in the City of Rockingham are here to stay after council voted against a motion to reinstate weekly collections.
Rate rises on the way for Rockingham, Mandurah ratepayers
Rate rises are on the way for Rockingham and Mandurah ratepayers.
Harvey Police call on witnesses to serious crash
Police are asking for the public's help as they investigate a serious crash in Harvey.
Men allegedly under the influence of alcohol when boat crashed under Mandurah Estuary Bridge
Two men have been charged over an alleged boat crash in Mandurah.
Works underway on 26 new social homes in Kwinana
Construction is underway on 26 new social homes in Kwinana.