They are not very big.
But once they hit the ground the damage they can cause is quite extensive.
"We've had tires from our units and other agencies units' spiked-causing damage to the tires," said Cpl. Cesar Saenz.
Just one of these homemade spikes or caltrops has ripped numerous tires completely apart.
Police told Action 4 News that smugglers have spent years perfecting these spikes and no matter how you throw them they will always land spike up.
One Valley lawmaker is now trying to make possessing these spikes illegal.
"It is very lethal, very simple, and needs to be stopped right away," said State Representative Aaron Pena.
The bill, which is still being tweaked, will allow law enforcement and military personnel to carry these small weapons.
But for others-they would have to pay a hefty price for having these spikes in their possession.
"We simply want to make sure that somebody pays a severe price for endangering the lives of our officers," said Pena.
Hidalgo County Sheriff Lupe Trevino said if these spikes get classified as a 'deadly weapon' it would allow his men and any other agency to return 'deadly force' during pursuits.
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