A mum has issued a warning after repeatedly coming across some 'strange' markings on the windows of her car.
Laura Morgan, from Wallasey, first noticed the 'X' marks being drawn on her car a couple of months back - and thought it was her children that were responsible at first.
However, after taking a closer look and realising that it was only happening overnight, she knew this couldn't be the case - and instead feared that it was a sign of something more 'sinister'.
Liverpool Echo reports that pictures show two cross marks that had been etched onto her car, which she parks outside on the street near her home.
Some believe that they're a sign used by thieves and burglars to communicate with each other on who to target.
Laura told the 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 secret codes like these are often used by criminals to identify potential homes to rob.
For example, an X means that the property is a "good target", while a circle with an X through it means that there possibly isn't anything worth stealing from the home.
The Safeguarding Hub, which offers advice on how to protect your home from burglars, 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."
The spokesperson also said that the strange marks shouldn't be ignored - especially if they're spotted on the home of an elderly or vulnerable person.
Security company Keytec also said that these marks were supposedly a "code" amongst criminals that can determine the kind of person that lives at the property.
They added that chalk is the most commonly used substance to make these markings, because of how easily it can be removed.
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