Look, here's how it goes. You can cite somebody else's work in your writing provided you give them full and proper credit in your footnotes (or endnotes) and bibliography. You can use direct quotes of up to 250 words in your work from someone else's work, provided you attribute it. However, note that 250 words is pushing the limit buddy, especially if you are pulling from an article rather than a book. This includes work found on the Internet, whether it is on websites, blogs, whatever. Somebody wrote it and that work belongs to them. It is far better to be overly cautious in this matter and attribute much rather than risk getting slapped with a plagiarism suit. Those are expensive and if you write for a living, will likely cost you your job, and most certainly your reputation. By the way, about those direct quotes. You're a writer, it's what you do. You're good with words. Rephrase that material in your own words (still attribute to the source, but rewrite). Too many direct quotes in your text and you look like you don't have a thought in your head. Not good.
I can't imagine why professional reporters think they won't get caught at the worst sin in the writing world. School kids use programs now that rate with a quick Internet review whether their writing includes plagiarism. Popular authors are able to easily track whether their work has been stolen or not. And writers do keep track of their work. I once (no plagiarism here, by the way) wrote a blog post about the top ten children's books (in my opinion). In less than a week, one of the authors mentioned had my glowing review of her kids book posted a link to my blog post on her website. Writers do watch. Computer systems keep track.
Be wise. Don't plagiarise. It's that simple. Really.