It could be they discovered the alarm the same way I did, but in their case, the bad guys heard the alarm too.
Check this out:
"Irene Bryant was killed by a blow to the left side of her head, the
medical examiner in Chapel Hill, N.C., said Tuesday.
Her body was recovered about 30 yards from the couple's SUV, which was
found parked near a hiking trail.
Investigators said that a check of phone records showed a call to 911
was made from the Bryants' cell phone on Oct. 21 from somewhere in the
area, but the call did not go through."
More at http://www.wyff4.com/news
