A police spokesman said they received reports of three break-ins to vehicles parked in Rectory Road, Shoreham and Southwick Street and Manor Close in Southwick between Saturday night (December 8) and the early hours of Sunday.
A van parked in Rectory Road had more than £1,000 worth of Christmas presents stolen from it, said police.
The spokesman said an attempted vehicle break-in was also reported in Oldfield Crescent in Southwick.
Police are asking vehicle owners not to leave any property in their vehicles and to park their vehicles in a well lit area and make sure they are locked.
If anyone has any information about the break-ins contact police by ringing 101 or email [email protected] quoting serial 266 of 09/12.