The number of metal thefts in a Worcestershire town has increased during the past few weeks, police say.
West Mercia Police said it had received 10 reports of lead flashing being taken from homes in the Church Hill North area of Redditch on Thursday.
Another 13 reports of lead being taken from roofs and elsewhere were made during Monday and Tuesday, with homes in Greenlands and Ipsley affected.
Police said more than one individual or groups appeared to be involved.
Insp Ian Joseph said the price of metal was particularly high at the moment and the number of thefts increased along as prices rose.
"Derelict properties are particularly vulnerable and owners need to consider their security arrangements," he said.
"We are increasing our patrols in the areas that have been worst affected but we need people to remain vigilant and report any suspicious activity as they see it happening."