It’s a handwritten note that prompted panicked calls to police over fears a girl’s welfare was under serious threat.

Yet those who dialled 911 in California last week were unaware the makeshift sign in the back window of a car suggesting a young child had been kidnapped was simply a prank on the girl’s mother driving the vehicle.

“HELP ME SHE’S NOT MY MOM!! Help!!” the note read, prompting California Highway Patrol South Sacramento to send out multiple officers and a dog squad after concerned bystanders called in.

The note which prompted a huge police response. Source: CHP - South Sacramento More

The vehicle was pursued and pulled over with authorities quickly realising it was all a hoax.

“It was determined that the juvenile had made it all up and thought it was a fun thing to do,” California Highway Patrol South Sacramento said in a Facebook post.

“The mother was unaware of what her daughter was doing and after it was determined that there was no foul play, the mother and daughter were allowed to leave the scene.”

Police issued a warning over the incident, urging parents to be vigilant to their children’s actions in the back seat.

California Highway Patrol South Sacramento said six units had been sent out for the incident and it was a waste of valuable police resources.

The force used the hashtag #notfunny to end their post.

“This is a reminder that parents need to be aware of what their children are doing in the back seat at all times,” the post said.

One commented they hoped the child was spoken to about the ramifications of their behaviour.

“Playing like that is not cool. [There’s] kids really out there missing and every second is crucial in finding them,” another said.

“What a waste of cops’ time for a prank. They could have been saving someone who really needed help.”

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