Police in Lincoln are asking drivers in Bracebridge Heath and Witham St Hughs to be vigilant due to thieves operating in the areas.
There have been a number of thefts from cars in the two south Lincoln villages in recent weeks.
On April 21 alone, police received five reports of thefts from vehicles in Bracebridge Heath.
Three of these happened on Salisbury Drive, with one on Canterbury Road and another on Wells Drive.
On April 24, three more incidents were reported in Bracebridge Heath, with two on Gloucester Close and one on Carlisle Way.
Two incidents were reported in Witham St Hughs on Greenfinch Crescent and Moorhen Close on March 31 too.
Items stolen include sat navs, electronics and cash.
Police are reminding residents not to leave valuables in the car when unattended, and asking anyone who saw any suspicious activity on these dates in the area to call on 101, or Crimestoppers anonymously on 0800 555 111.