Google has acknowledged an issue with indexing and surfacing content from news publishers in Google News. This may result in a decrease in traffic from Google News. Google is working on fixing the issue and has stated that the next update will be provided within 24 hours. This bug has caused significant traffic problems for some publishers. If your site is in Google News and you have experienced a drop in traffic recently, it may be related to this indexing bug. Google is aware of the issue and is working on a solution.

source: Google confirms bug with Google News impacting publisher traffic