Those arrested have been identified as Sonu (24), Faizan (32), Azad (35), Naushad (37) and Aftab.
The police have recovered looted copper wire, electric motors, pump and other articles of PWD from their possession.
"We made several teams to investigate the case after we got information about the robbery at PWD office in Pitampura. Complainant Raj was made hostage along with some workers by about 8-10 criminals who decamped with electrical goods," a senior police official said.
"On scanning the CCTV cameras footage, we found images of the assailants and began a manhunt. Cops first nabbed Azad followed by Faizan and Aftab. During interrogation, they confessed to the crime and disclosed the location of other accomplices, who have also been arrested," the official said.
The robbery was carried out in the wee hours on June 6.
One of the accused Sonu also confessed to have committed a theft of electronic batteries and other electronic goods from Jahagirpuri, official said, adding, police have recovered 44 electric batteries.