If You See These Marks Near Your Door or Mailbox, Call the Police
Unusual marks outside a home aren’t what most people expect to notice. Still, police in both the U.S. and U.K. report that they show up more often than many realize. Symbols in chalk, strips of tape, or small objects like stones and stickers have been found on doors, fences, and mailboxes. At first glance they look meaningless, but investigators warn they’re used as signals.
Why does a chalk line or sticker matter enough to call law enforcement? Officers say those marks often aren’t random. They serve as quiet messages between criminals, and that’s why they take them seriously.
The Secret Codes Burglars Use
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Across Essex, Manchester, and parts of the United States, police have traced odd markings back to burglars scouting neighborhoods. A Lanarkshire Police report explained that these signs can be a kind of shorthand between criminals: a symbol for an easy target, a different one for a home with alarms, and another for vulnerable occupants like the elderly. When you see stuff like chalk, tape, or even kidney beans scattered by a doorstep, it may not be random at all.
Officers warn that houses marked as “good targets” often have poor security or valuables in plain sight. On the other hand, a mark signaling “too risky” usually means visible cameras or alarms made intruders reconsider. Either way, these symbols act like coded notes, and spotting them early gives homeowners a chance to respond before a crime happens.
Where These Marks Usually Show Up
Reports show that burglars favor subtle spots like the base of mailboxes, fences, or the sides of gates. Some homeowners have discovered a string tied to garden fences, stickers put on trash bins, or tape placed neatly over a keyhole.
Each method is designed to see if someone notices and removes it. If the object or mark stays for days, it signals the property may be unoccupied or overlooked. In other cases, small stones are left by doors, or flyers are wedged into cracks on a gate.
Failing to move or remove these items can send the wrong message to anyone watching. That’s why police encourage people to pay attention to even minor changes around their entrances.
What To Do When You Spot One
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The first step is to take photos of any marks, stickers, or objects that look out of place, and make a note of when and where you found them. Share this information with local authorities. Calling your police department’s non-emergency line is usually recommended unless there’s an immediate threat. Law enforcement may decide to increase patrols in the area or investigate further.
Next, erase or remove the marking. Chalk can be washed off, tape peeled away, and objects cleared. This prevents intruders from relying on those signals and shows someone is paying attention. Neighbors should also be alerted, since burglars often mark several homes in the same block to test which ones are being monitored.
Don’t Make Your Place an Easy Target
Spotting marks is only part of the response. Strengthening your property’s defenses reduces the chance of becoming a target in the first place. Police and security experts recommend installing visible cameras at entry points, using smart alarms that notify you instantly of suspicious activity, and upgrading locks to high-security models resistant to tampering.
Outdoor lighting is another effective deterrent. Criminals prefer to operate unseen, so motion-activated lights and trimmed landscaping remove the cover they rely on. Regularly checking doors, windows, and gates also closes off easy access. A small investment in visibility and monitoring pays back by discouraging intruders from ever marking your home.
The markings themselves may look minor, but their meaning is serious. In Manchester in 2021, kidney beans placed on doorsteps signaled empty homes. In Essex, chalk codes indicated whether a property had an alarm or vulnerable occupants.
In the U.S., stickers and flyers have been tied to attempts to test occupancy. Each report underscores the same lesson: spotting these early warnings and acting quickly can prevent a burglary.