Zaelti was an operative who was among a crew of spies, along with McLelland, working for the Merovingians to infiltrate the Zionite faction.
Chapter 7.3.3-7.3.4[]
When Zion found and captured the undercover Merovingian crew who had relayed The Oracle's kill-code to a spy inside Zion --apparently someone on the Oracle's security detail. Questioning of one the captured crew, McLelland, helped Zion identify the spy himself--an operative named Zaelti--but the kill-code was not found in his possession.