A string of car break-ins across the city has Bowling Green police officers putting residents on the alert. So far, 18 people have been identified as suspects in 40 or more break-ins and are awaiting indictment, according to Bowling Green police Officer Penny Bowles. The number of break-ins actually could double and there may be other people involved, Bowles said. Car break-ins typically spike around holidays and in the summer when juveniles have more free time on their hands, she said. The suspects are a combination of juveniles and adults. Two were arrested Sunday and charged with breaking into cars parked in lots on Mel Browning Road. Police arrested Joseph Derek Simmons, 18, and Nicholas Allen Cole, 22, no addresses available, and lodged both in Warren County Regional Jail. Simmons is being held on a $10,000 cash bond. Cole is lodged with a $5,000 cash bond. Those stealing items from cars dont always have to break-in. While some vehicles had windows broken so entry could be gained, many of the vehicles were left unsecured, police said. People are taking easily pawnable items like compact discs and boom boxes, Bowles said. The CDs dont have serial numbers and cant be traced by police if they are taken to pawn shops. But other items do. Bowling Green police get the serial numbers on all items pawned to shops in the city; officers enter those numbers in the computer and see if they match the serial numbers of any items reported stolen. If they do, we notify the owners and they can retrieve the items from pawn shops, Bowles said. While pawn shop owners are required to provide police with those serial numbers, they arent required to notify police when someone is pawning an inordinate amount of items. They have to make a living, Bowles said in defense of store owners. To prevent cars from being an easy target for thieves, police suggest:Locking up every time you leave the vehicle;Removing all valuable property from vehicles and truck beds;Parking in well lit areas. But Bowling Green resident Jerry Wayne Lawson said hes not sure such tips always will help. Lawsons vehicle was broken into Thursday or Friday while it was parked outside his home in the 1700 block of South Sunrise Drive. I think they are breaking into a lot of vehicles with tinted windows, not even knowing what might be there, Lawson said. They smashed in Lawsons window and took CDs and tried to take the CD player but left it behind after seeing that it probably wouldnt work without all of the parts. Lawson said there may be help in locating the thief or thieves since a cigarette lighter with a name on it was left behind.