Major development tonight in the story we've been following here on world news tonight involving lead in the water in Flint, Michigan. Tonight a major investigation launched the governor of Michigan asking the White House to declare a federal disaster. This evening many asking what did authorities know and when did they know what ABC's Alex pressed back on the case at limelight and Elaine. This there's not a light. Tonight at Michigan governor Rick Snyder and possibly other state officials under investigation after an unprecedented toxic water crisis in Flint. The Michigan attorney general today launching a formal investigation to determine if any laws were violated. And why it took authorities is so long to respond. Saying in a statement the situation in Flint is a human tragedy in 21 century America. No one should have to fear something as basic as turning on the kitchen faucets angry residents now testing their children for lead poisoning. Tell us how long we gotta keep suffering that is the frustration growing since winning fourteen when the city of Flint is not paying for water from lake you're on and began to process water from the Flint river to save some nineteen million dollars. It wasn't until more than a year later at that officials declare the water unsafe. This week the Governor Snyder deploying the National Guard volunteers delivering bottled water and tap water filters to residents. And David the governor even asking President Obama to declare a federally emergency in Flint there's already a FEMA team on the ground assessing the situation David. Alex thank you.