Before posting a new thread with a news article, use the Advanced Search function in the forum software. Pick a unique name or location or word in the article as the search word/phrase and then set a "Message age" based on how long ago you think the event occurred. In a matter of a minute or less you will learn whether there is an existing thread about the topic.
Before anyone asks the reasonable question, I have been doing this on various discussion sites for years. And when I did post a duplicate thread, invariably it was because I didn't do a search first.