By Daily Mail Reporter PUBLISHED: 08:05 EST, 21 March 2013 | UPDATED: 08:06 EST, 21 March 2013 A man charged with killing a woman and raping her 10-year-old daughter after a carjacking at a New York mall last week was able to remove his court-ordered electronic monitoring bracelet before carrying out the brutal attacks. A senior probation officer told a New York court earlier this week that David Renz, 29, managed to cut the device from his ankle and put it back together so quickly that it didn't prompt BI, the company in Colorado that makes the monitors, to notify court officers in Syracuse.
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Suspect David Renz was arrested in January on child porn charges
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He was fitted with an ankle monitor but on Thursday evening he managed to remove it without alerting authorities
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He has been charged with committing murder, rape and kidnapping while he should have been wearing the bracelet
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A security expert denies the device is at fault in this case
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He questions police protocol which meant the alarm wasn't raised for short interruptions in the device's signal
was no alert to probation officers from @placeholder until 11:30 p.m. That only