Police are warning residents to be vigilant after a spate of four linked burglaries took place in Pinner on January 18 between 5-6pm.
Two of the attempted burglaries took place on Cannonbury Avenue and one burglary in East Towers and West Towers respectively.
Several burglaries involving the same method have taken place across the area in the past month.
The lone suspect uses a ladder, bin or drainpipe to access flat roofs, before gaining entry to properties through a first-floor window.
Valuables such as jewellery and expensive designer items are typically stolen.
The Pinner Safer Neighbourhood Team want to highlight the importance of preventing access to your garden from every side, and ensuring that ladders, bins and other items are secured away from your property, so they cannot be used to climb on.
They advise residents to consider affixing perimeter edging or carpet gripper to the edge of flat surfaces and apply anti-climb paint to drainpipes.
Ensure windows in unoccupied rooms are closed and locked, and do not leave valuables within sight or reach of windows and doors.
At the time of writing, no related arrests have been made. Any witnesses or anyone with information can call the police via 101 or contact Crimestoppers anonymously.