A 29-year-old man and a 17-year-old boy, from Irthlingborough have been arrested in connection with the theft of reels of wire.
The theft took place in Addington Road, where two wheelie bins were used to transport the reels in an early morning getaway.
Police believe that sightings of two men on the A6 section of Station Road could be linked to the investigation.
A spokesman for Northants Police said: "Police investigating the theft of reels of wiring in Irthlingborough are appealing for witnesses who may have seen two men pushing wheelie bins nearby.
"The theft took place at a property in Addington Road between 6.30am and 6.50am on Wednesday, February 24, with the stolen items carried away in wheelie bins.
"It is believed the offenders made their way along the A6 towards Station Road, and officers are appealing for anyone who may have seen them at any point on their journey to get in touch."
Witnesses or anyone with information about the thefts should call Northamptonshire Police on 101 quoting incident number 21000108334
The spokesman added: "A 29-year-old man and a 17-year-old boy, both of Irthlingborough, arrested in connection with the thefts have been released under investigation."