The police had tracked their mobile phones and nabbed them yesterday. Six mobile phones were recovered from their possession.
Extortion was the motive of the crime, police said.
Umakant Panda (23), Sonu Nigam Pradhan (32) and Tofan Pradhan (24), were arrested by special squads constituted for the purpose. Yjey hailed from the Patkura area of Kendrapara district, said Soumendra Priyadarshi, Inspector General of Police (central Range).
On Thursday, the miscreants had gunned down Debashis Sahu (28), an electrical engineer of a private power infrastructure company, near Bada Mangala locality in the heart of the town.
A motor bike and a country-made pistol used to execute the crime were also recovered from them.