LYNN – A 22-year-old Lynn man has a lot of explaining to do after he was caught on camera Tuesday smashing up four cars at his workplace, Boston police said.Preston Clark was arrested and charged with willful and malicious destruction of property over $250.Police responded to Clark’s employer, the Herb Chambers auto dealership at 1168 Commonwealth Ave. in Brighton after fellow employees found that four cars were seriously vandalized, police said.The damage included smashed windshields, broken mirrors and multiple dents and scratches, according to police.It didn’t take long to identify a suspect after employees viewed surveillance video and allegedly observed Clark vandalizing the cars on Monday night. The motive behind the vandalism is unclear.