DOG owners are urged to be extra vigilant around their properties after Dunbar residents spotted mysterious chalk markings and pebbles outside their homes, in what some believe could be the work of potential dog thieves.

Cathy Mccue, from the town, posted about the issue on social media after she heard knocks on her door at 4.45am on a Sunday morning.

Cathy was in her hall at the time, walking off a cramp, when she heard the knocks, saying she “near had a heart attack” in fright.

Other residents in the town have since said they also received knocks on their doors or rings on their doorbells that same night.

One man said that he had an arrow chalked on the path outside his back gate and thought at the time it was a children’s drawing.

Another woman received two rings on her doorbell, with no one there when she looked; she then discovered two painted pebbles left in her plant pots.

A third woman said that she received two knocks on her door the following night while she was watching television, adding that someone was pacing outside her house before they knocked.

It is claimed by some that dog thieves will knock on a door twice before running away; if a dog barks, they will come back and leave a mark, which can be in the form of a chalk marking or pebble, noting that the home has a dog worth stealing.

The marks have appeared in other parts of the UK, leaving some homeowners paranoid and “losing sleep”.

A woman from Woodbridge in Suffolk said that it was not just chalk that was used – thieves also used cable ties and left gates open.

She added that they could also knock on a door to see if the owner inside would like any work done, a way of them finding out if they had dogs inside the property.

Cathy said the marks were “things that most people wouldn’t even look at twice”, calling the people leaving them “devious”.

The Courier has contacted Police Scotland for comment.