A mum has put out a warning after claiming to have consistently found bizarre 'X' markings on her car windows.
Laura Morgan from Wallasey began to notice the marks on her car about two months ago.
The photos showed two crosses drawn onto the window of her car, which at the time was parked on a road.
The markings initiated fears of sinister activity, with some thinking they were being used by wannabe robbers and thieves to communicate with each other.
Laura told the Liverpool Echo : "It took almost two months for me to even realise what was happening, I thought it was kids at first, but it was happening between the hours of 10pm and 6am."
Earlier this year, The Mirror reported that some criminals use secret markings to indicate things about a property.
For example, an X means that the property is a "good target", while a circle with an X through it means that there is nothing deemed worth stealing.
The Safeguarding Hub - which shares home protection advice and information across the UK - previously said: "Between us, we have a fairly extensive knowledge of burglary.
"We have spent many hours speaking to distraught victims, visiting crime scenes and dealing with burglars. We have actually seen and experienced these symbols being used by criminals.
"This is not to say that this is a common practice between bands of thieves, for most burglars work alone. We do not want to scaremonger and we can say confidentially that the use of these symbols is very rare.
"But, if you are a caregiver to an elderly or vulnerable person and spot strange marks outside their home, do you really want to dismiss it out of hand without just ensuring that the symbol is legitimate?"
Security firm Keytek has also highlighted the issue saying: "These ‘robbery markings’ or ‘burglar signals’ are basic sketches and forms that are supposedly used as a ‘code’ to determine whether a house is worth targeting.
"These illustrations are also supposed to indicate to other thieves what type of person lives at the property, such as whether the residents are vulnerable, elderly, or live in a single-family home."
It added: "Chalk is the main material burglars use as it is easily removed and not as noticeable as materials such as spray paint markings outside the house.
"As well as burglar chalk signs, burglars mark houses with almost anything they can; it may be a small blob of paint or a piece of string tied around a lamppost."
