Several vehicles were broken into over a 24-hour period – sparking police to warn drivers to be vigilant.
Vehicles parked in Bushey were targeted by thieves on Monday and Tuesday (November 28 and 29).
Police say two incidents were reported in each of Ivinghoe Road and The Squirrels, as well as one in Little Bushey Lane and one in Stirling Way, Borehamwood.
In some cases, the suspects have successfully stolen items including money from the vehicles.
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Officers have been carrying out additional patrols in hotspot areas of Hertsmere but have urged residents to be “vigilant”.
This includes reporting anyone acting suspiciously around vehicles by calling 999 or calling 101 with any information to help with investigations into vehicle break-ins.
People are also being encouraged to check their vehicle is vehicle locked and secured and valuables removed.
Hertfordshire Constabulary was recently criticised after figures revealed the number of people charged in connection with vehicles being stolen in Hertfordshire.
Just over 1,200 were stolen in a 12-month period - but only around 2% led to charges.
Read more: Police blasted over 1,200 car thefts and 'shameful' charge rate
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