Police in Lincoln are asking people to be vigilant after several properties in the city have been targeted by lead thieves.
Lincolnshire Police say properties in Clarence Street (pictured) and Burton Mews have been targeted and lead has been stolen from porch roofs.
Officers are looking for two men on bicycles in dark clothing who have been seen in the area acting suspiciously and may be connected.
The price of lead has quadrupled in the last four years, currently standing at £1,800 a tonne, having hit record highs of £2,400 a tonne in September 2010.
Just four years ago it was over £400 per tonne. Demand for lead is at an all time high. Some analysts are blaming the Chinese and battery makers.
Anyone with any information can call Lincolnshire Police on 0300 111 0300 or give information on criminals operating in their area anonymously to Crimestoppers on 0800 555 111.