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The F.B.I. has joined the investigation into the Flint water crisis, four months after Michigan Governor Rick Snyder acknowledged that the city's drinking water contained dangerously high lead levels. The Detroit Free Press reported that "federal prosecutors are 'working with a multi-agency investigation team on the Flint water contamination matter, including the FBI, the U.S. Postal Inspection Service, EPA's Office of Inspector General, and EPA's Criminal Investigation Division.'"

There are several investigations of the crisis underway, including one commissioned by Snyder and another being overseen by Michigan Attorney General Bill Schuette. Tomorrow, the the House Oversight Committee will begin its hearing on the Flint water contamination–though, as the Huffington Post notes, that process has been criticized because Snyder is not actually being called as a witness to testify.

Contamination of Flint's water began in April 2014 when the city switched its water supply from Lake Huron to the Flint River, possibly to cut costs. The corrosive water from the new source leeched lead from the pipes in many Flint homes, and posed a serious risk of lead poisoning for Flint residents, especially those with children. The city has begun handing out water filters and bottled water recently in an effort to assuage the public health crisis.