Violence broke out at Okwagbe community in Jeremi 3, Ughelli south local government area of Delta state as Jeremiah Oghoveta, a chairmanship aspirant, was stabbed to death.
One Tete Pippah was said to have attacked Oghoveta after an argument ensued over allegations of hijack of electoral materials by a side.
Oghoveta reportedly disagreed with some other party members, asking why materials would be hijacked.
He was leaving the scene when his attacker stabbed him on the neck and fled the spot, leaving him dead.
Andrew Aniamaka, spokesman of the Delta state police command, confirmed the incident, saying the command had already started an investigation into the incident.
He said efforts were in place to arrest Pippah, who was already on the run.
The congress is holding in the 25 local government areas of the state and all over the country.
The Adamawa state chapter of the party had postponed its own ward congress following protest by some stakeholders.
Violence have been recorded in Rivers, Oyo and Imo.