They accuse Google of dropping them out of their search results (or at least lowering their pagerank) if they ask Google to remove their articles from Google News. So the accusation is abuse of a dominant position.
As far as the newspapers are concerned, news search and web search are separate business, but I doubt google should be forced to folllow the same definition. Abuse of dominant position requires one to have monopoly power (granted, google has it on web search and plausibly also on news search) but also deliberately using that power to somehow hinder competitors. I am not sure that google should be required to keep newspapers on one index while removing it from other or to prevent changes on one index to be reflected on another (why should a company be required to keep completed isolated indexes?).