She didn’t know what it was -- until she went outside the next morning and found her mailbox pieces in front of her house.
"Somebody blew it up," she said.
A few blocks away, the same thing had happened to a neighbor, who found a mangled water bottle which had been converted into a homemade bomb.
Directions for making the devices are easy to find on the Internet.
"This could really, really hurt somebody really bad," Heath said.
Both incidents appear related because they were so close and both occurred the night of June 1, police said.
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"It's very possibly kids being kids, but it's dangerous," Sgt. Craig Teague said. "It's going to get somebody hurt."
The second neighbor caught images of the bomber on a surveillance camera.
After placing the explosive device in the mailbox, the video shows the vandal threw another device inside a Jeep parked in the man’s driveway. That device did not explode.
Police said they want to find the culprits before someone gets hurt.
"It's really scary," Heath said. "It gives you goose bumps. You start thinking, 'Do I have any enemies?'"
The two houses were apparently picked at random, police said.