A Chula Vista man credits a small device on his house for helping police catch a group of thieves.
Emilio Valdez says he installed a motion sensor alarm in addition to security cameras.
"It's just a motion sensor," he said. "You put one outside, the sensor outside and it alerts you wirelessly upstairs and I put the alarm in my room."
The alarm woke him up at 3:30 a.m., when thieves were prowling around his neighborhood on Porch Swing street.
"I actually did yell at him," Valdez said. "I said some words I can't say on TV but I was yelling at this guy."
A neighbor called police and Valdez's security cameras caught two police cars racing up their streets chasing the thieves. Valdez says they arrested four people, and hopes everyone takes the extra step to protect their homes.
"Oh I love this," Valdez said. "Anybody in this area I get to find out if they're messing with my property and stuff so it's good thing."
Valdez bought his motion sensor off Amazon for $30, and calls it the best $30 he's ever spent.
