Probably investigators had gotten some them to cooperate in exchange for a plea deal, and today they were formally charged as part of the deal... and the journalists used the word "arrested" instead of "charged" to spice up the story a bit.
Perhaps, but one of the responsibilities of a journalist is to get it right, absolutely right, every time.
In the 20th Century, it became much more important to be first than right.
Now, it’s more important to promote a social or political view than it is to get it right.