Six people had been ambushed and killed near Peta on Saturday,Hela Police Chief Inspector Teddy Augwi told the newspaper.
The victims'relatives retaliated with rifles the next day,killing between 16 and 18 people at Karida,including pregnant women,he said.
"This is not a tribal fight where the opposing villagers face each other on field,"Augwi told the newspaper.
"This is a fight in guerrilla warfare,meaning they play hide-and-seek and ambush their enemies."
Many villagers had fled the violence,Hela Administrator William Bando told the newspaper.
It was not immediately clear if any suspects had been arrested. Papua New Guinea Police spokesman Superintendent Dominic Kakas did not immediately respond to a request for comment on Wednesday.
Tribal violence is common in Papua New Guinea's interior,where villagers avenge relatives in retaliation known as payback.
The country maintains the death penalty in law but there have been no executions since 1954. Parliamentarians for Global Action report nine death sentences were imposed in 2018 and 20 people remained on death row.
AP,The Age