Would-be thieves attempted to steal keys by poking a three-foot long bamboo cane through a cat flap of a house in Milton Keynes.
It happened between 6.45pm and 10pm on Wednesday,in Tiree Court, Newton Leys, but nothing was stolen.
Det Con Samantha Reynolds, the investigating officer, said: “I would like to speak to anyone who may have any information about this incident and would urge them to come forward and speak to me as soon as possible.
“Keeping keys in a visible place near to doors and windows should be avoided as opportunist thieves may attempt something like this.
“Keeping them out of sight and secure makes you less of a target.”
If you don’t want to speak directly to the police, you can contact Crimestoppers anonymously on 0800 555 111.
No personal details are taken, information is not traced or recorded and you will not go to court.