Two nine-year-old girls have gone on a destructive rampage and hurled abuse at a pregnant woman at a busy Gold Coast shopping centre.

Video shows the two girls jumping on the roof and windscreen of a car at Westfield Helensvale, moments after punching a security guard and threatening to attack shoppers.

"This is our car so get f-----! Get f-----, you -----," one of the girls said.

The girls were seen jumping up and down on the car in the car park of Westfield Helensvale. (Nine/Supplied)

In the video, a security guard for the centre attempts to diffuse the situation, by seizing one of the girl's scooters.

"If you take it I'll bloody kill you. Give me my f------ scooter," one of the girls said.

Witness Jonni Row told 9News one of the girls spat on the security guard.

"They were just screaming 'we know the law you can't touch us'."

A security guard confiscates a scooter from one of the girls in an attempt to diffuse the situation. (Nine/Supplied)

Police later put the girls in the back of a patrol car and took them home to their foster parent's house.

"Their tail was between their legs as soon as the cop car pulled up," Ms Row said.

Witnesses have told 9News the ordeal went on for more than 90 minutes, and began inside the shopping centre when the two girls became involved in an altercation with an elderly woman.