Two teenagers from Lewes are being questioned by police on suspicion of trying to break into a home.
Police were called to reports of two people trying car doors and acting suspiciously in Stanley Road, Brighton, shortly before 4.30pm on Wednesday August 14.
The teenagers had also tried to get into a basement flat in the road through a slightly open window and the front door.
One of the suspects was white and wearing a white t-shirt while the other was dark skinned and wearing dark clothing.
Officers searched the area and in Winchester Street they found two teenagers who fitted the description of the suspects.
When they tried to speak to the them, one of the suspects ran off but a special constable chased and arrested the man in nearby Lorne Road.
Sussex Police launched Operation Magpie to tackle burglary across the county.
An 18-year-old man and a 17-year-old male youth, both from Lewes, are being questioned on suspicion of attempted burglary.
The 18-year-old is also being questioned on suspicion of theft.
Anyone with information should call 101 quoting serial 1047 of 14 August or the independent charity Crimestoppers anonymously on 0800 555111.