Two motorcycle-borne assailants shot at two project engineers - Brajesh Kumar and Mukesh Kumar near Shivram Chowk while they were supervising road construction by M/S BSCCNC, a road construction company, Deputy Superintendent of Police Dilnawaz Khan said.
Both were taken to Darbhanga Medical College and Hospital (DMCH) where they were declared as "brought dead", he said.
Non-payment of levy was said to be the motive behind the murder of two engineers, Khan said.
A probe was on.
The construction company had sought protection five days ago after receiving a ransom demand by unidentified persons and police deployment had been at the construction site in view of threat, but despite that its two engineers were fatally attacked by the unidentified gunmen, he said.
Superintendent of Police A K Satyarthi was camping on the spot.