Thieves broke into two cars in Piries Place Car Park in Horsham town centre and stole items on the night of New Year’s Eve.
One of the thefts happened at some time between 9.30pm on Wednesday December 31 and 2.30am on Thursday January 1.
The offenders broke in via a side window and stole two jackets and a rucksack.
On the same night, a second car was broken into and a pair of brand new £150 Nike trainers and a holdall containing blue jeans and Diesel aftershave were stolen.
Police added that during Wednesday evening (December 31), the bonnet of a car parked in the same car park was dented, as if someone had sat on it, but no attempt had been made to steal anything from the car.
Police are appealing for witnesses. Anyone with information can contact police via firstname.lastname@example.org,police.uk or by calling 101, quoting serials 312 or 903 of 1/1.