The West Bengal CID has bustedan illegal arms manufacturing unit in West Bengal's North 24 Parganas district and arrested two persons, a senior officer of the agency said on Thursday.The illegal arms manufacturing unit was set up at a flat in Nimta area, he said.Two fire arms have been seized during the raid, conducted by a joint team of CID along with Nimta police, at the flat on Wednesday night, he said."We had a tip-off that a customer was arriving there to procure arms. Besides arresting him, we nabbed another person at the illegal arms factory," the officer said.The CID has launched a search for others involved in making illegal weapons at the flat, he added.