Seaford saw a spate of vehicle crime during the early hours of Thursday.
Between 4am and 4.30am, several vehicles were broken into and searched in Juniper Close, Willow Drive and Rodmell Road.
At about the same time, a garage in Willow Drive was also entered, where an untidy search was carried out.
Three men wearing dark hoodies were seen running from the area.
Sussex Police believes up to six vehicles were breached, though it seems there were only two cases of theft.
Sergeant Stuart Mullins said: "It appears these vehicles were not secure and that the suspects had been trying door handles in the surrounding area."
Sgt Mullins said the incidents underlined a message to always lock vehicles, no matter where they are left or even if just for a short time.
The police has reiterated that valuables should not be left in vehicles and property should be hidden from view.
Anyone seeing suspicious activity around unattended cars should call 999 immediately.
Anyone with information about Thursday's crimes should email firstname.lastname@example.org or call 101.
Alternatively, call the independent charity Crimestoppers free and anonymously on 0800 555 111.