Guelph Police are reminding car owners to lock their vehicles after 18 unlocked cars were robbed over the last three days. 

"This crime, as easily avoidable as it is, is probably the most common crime we deal with," said Const. Mike Gatto.

Close to 500 thefts in cars were reported to Guelph Police in 2013, said Gatto, adding that more thefts tend to occur when there is nice weather. 

Gatto said people who target unlocked cars do not want to damage the vehicles. Rather, they want to scrounge what they can – from change to sunglasses and cell phones. 

'There's a great many more of these thefts from cars that go on that people just choose not to report.' - Guelph Police Const. Mike Gatto

"They don't want to make noise. They want to stay invisible as they go around checking cars," said Gatto. 

The problem is citywide Gatto said, with theft in cars committed by people of all ages in neighbourhoods across Guelph. 

The best line of defence? It's obvious, Gatto said. Lock your car. And if your car is broken into, you should call police

"There's a great many more of these thefts from cars that go on that people just choose not to report," Gatto said, adding that many go unreported because victims are embarrassed. 

"They know darn well it wouldn't have happened if they would've locked their car."