A man and a woman have been arrested after they allegedly broke into a home, changed the locks and claimed to be the owners when questioned by police.

Key points: A man and woman have been charged with aggravated serious criminal trespass

A man and woman have been charged with aggravated serious criminal trespass The pair faced court on Wednesday

The pair faced court on Wednesday The owner of the house was in the process of moving when he discovered new locks on the doors

Police were called to the property on Wallace Street at Balaklava, in South Australia's Mid North region, about 10:30am on Tuesday.

The actual owner — who was in the process of moving house — had earlier returned to the home to find new locks on the doors and a couple inside, police said.

When officers arrived, the couple initially claimed they owned the property, police said.

"Officers established that the couple had actually broken into the home and changed the locks," police said in a statement.

The 40-year-old woman and 28-year-old man, both from Balaklava, were charged with aggravated serious criminal trespass.

The couple appeared in Elizabeth Magistrates Court on Wednesday.

The case has prompted police to urge the public to report any suspicious behaviour.

In a separate incident, police are investigating a shed break-in in the Riverland in which a power tool and another device were stolen.

Police said the theft at Monash occurred between Friday evening and Monday afternoon.

A pressure washer and a power inverter were taken from the shed.

Police have asked anyone with information to call Crime Stoppers on 1800 333 000.