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HOUSTON - When Astrid Sierra bonded out of jail last June for two counts of Aggravated robbery, one of her bond conditions was to wear a GPS ankle monitoring device.
"The offense which triggered GPS monitoring, she held a 12-year-old at knifepoint and threatened to cut him up," said Harris County Assistant DA Yasmeen Belal.
Police say the monitoring device didn’t stop Sierra from committing crimes.
The say on January 6, she stole a man’s pickup truck in the parking lot of an apartment complex at 6300 W. Bellfort.
"She asked him for a light for a cigarette. He was trying to find it, she got impatient, pulled a gun, ripped off his necklace ordered him out of the vehicle, and took off in his car," Belal said.
So how did Sierra commit this robbery when she was wearing a court-ordered GPS monitoring device around her ankle?
"She did confess to police when she was detained on these new charges she was able to take that monitor off with Vaseline," said Belal.
In all, prosecutors say Sierra used Vaseline to get the ankle monitor off three times.
While it was back at her house, Sierra allegedly held up a McDonald's and a Jack in the Box.
"The fact she was able to remove it so quickly definitely raises questions serious questions," Belal said.
Officials are calling Sierra’s crime spree extremely unusual.
They say they got no notification when she took the device off.
They theorize the strap may have been loose around her ankle.
If that’s the case, they say a pre-trial officer should have noticed that during one of her regular face-to-face meetings.
Pre-trial services tells FOX 26, they will get to the bottom of this to prevent it from happening again.