Oamaru police have concerns about the growing number of reports of people trespassing on private property in the town.
About 1am on Tuesday, two men, believed to be in their late teens or early 20s, were discovered by a man in the backyard of his Eden St address after he heard a gate open and went to investigate.
Police were called to the scene but the alleged trespassers had fled by the time officers arrived.
The report followed a similar one received by police on Tuesday. That incident took place on Monday night at the Kiwirail yards in Humber St, where a vehicle allegedly was tampered with.
Sergeant Tony Woodbridge, of Oamaru, said indications were the alleged act was carried out by a group of youths who were known to frequent the area at night and were known to police.
He said the most recent incidents were the latest examples of a growing trend that was of concern to police.
''Over the last couple of months we have had reports of youths hanging around the rail yards on Humber St.
"We have had tools stolen from areas around there in the past. It looks like a group of youths that we do know of, but for us to identify them it would be good if members of the public that had seen them could let us know ... it would be really good to catch them in the act.''
The area was monitored by North Otago Security, which reported any incidents to police.
Sgt Woodbridge said police had also increased their presence around Humber St.
''We certainly do patrol in the risk areas and that area certainly is a risk area.''
Anyone who had seen any suspicious activity around Humber St was encouraged to contact police.
