I've been watching Breaking Bad as of late, and I've got the final episode planned for tonight (so please, no spoilers). In Ozymandias and Granite State, we see Walter White going into hiding after the murder of his brother-in-law. I understand that he needed to flee his family after it was revealed to Walter Jr. that Walter was a Meth kingpin. But during Granite State, we all of a sudden see Skyler talking to the police about Walter. Later, we hear that Skyler has been thrown out of her own house, that the White residence has become a playground for adolecents and that Walter's crimes have been outed all over America.
Yet the DEA only has little puzzle pieces of evidence. Hank and Gomez have vanished, the Schrader house was broken into and Walter kidnapped his daughter: enough to know something's on, but nothing leading to Walt's secret identity as a drug kingpin. The only evidence that was there, if I remember correctly, was the testimonies of Marie, Skyler and partly Walter Jr.
Did they rat Walter out? Or am I overlooking some piece of evidence? What fueled the DEA investigation into Walter White and what did they have that was so concrete that they managed to press charges against Skyler?